[Storage][Blob] Flatten and simplify access conditions

Use a flattened conditions type `BlobRequestConditions` instead of current
nested one.  It replaces `ContainerAccessConditions` and `BlobAccessConditions`.
In addition, various conditions fields are renamed into simply `conditions`.
This makes it more convenient to pass in conditional request options.

the example

```js
{
  blobAccessConditions: {
    modifiedAccessConditions: {
      ifMatch: uploadResponse.eTag
  }
}

```

after this change becomes

```js
{
  conditions: {
    ifMatch: uploadResponse.eTag
}
```

sdk/storage/storage-blob/src/AppendBlobClient.ts

@@ -14,8 +14,8 @@ import { AbortSignalLike } from "@azure/abort-controller";
 import { BlobClient, CommonOptions } from "./internal";
 import { AppendBlob } from "./generated/src/operations";
 import {
-  AppendBlobAccessConditions,
-  BlobAccessConditions,
+  AppendBlobRequestConditions,
+  BlobRequestConditions,
   Metadata,
   ensureCpkIfSpecified
 } from "./models";
@@ -50,10 +50,10 @@ export interface AppendBlobCreateOptions extends CommonOptions {
   /**
    * Conditions to meet when creating append blobs.
    *
-   * @type {BlobAccessConditions}
+   * @type {BlobRequestConditions}
    * @memberof AppendBlobCreateOptions
    */
-  accessConditions?: BlobAccessConditions;
+  conditions?: BlobRequestConditions;
   /**
    * HTTP headers to set when creating append blobs.
    *
@@ -95,10 +95,10 @@ export interface AppendBlobAppendBlockOptions extends CommonOptions {
   /**
    * Conditions to meet when appending append blob blocks.
    *
-   * @type {AppendBlobAccessConditions}
+   * @type {AppendBlobRequestConditions}
    * @memberof AppendBlobAppendBlockOptions
    */
-  accessConditions?: AppendBlobAccessConditions;
+  conditions?: AppendBlobRequestConditions;
   /**
    * Callback to receive events on the progress of append block operation.
    *
@@ -146,17 +146,17 @@ export interface AppendBlobAppendBlockFromURLOptions extends CommonOptions {
   /**
    * Conditions to meet when appending append blob blocks.
    *
-   * @type {AppendBlobAccessConditions}
+   * @type {AppendBlobRequestConditions}
    * @memberof AppendBlobAppendBlockFromURLOptions
    */
-  accessConditions?: AppendBlobAccessConditions;
+  conditions?: AppendBlobRequestConditions;
   /**
    * Conditions to meet for the source Azure Blob/File when copying from a URL to the blob.
    *
    * @type {Models.ModifiedAccessConditions}
    * @memberof AppendBlobAppendBlockFromURLOptions
    */
-  sourceModifiedAccessConditions?: Models.ModifiedAccessConditions;
+  sourceConditions?: Models.ModifiedAccessConditions;
   /**
    * An MD5 hash of the append block content from the URI.
    * This hash is used to verify the integrity of the append block during transport of the data from the URI.
@@ -386,16 +386,16 @@ export class AppendBlobClient extends BlobClient {
     options: AppendBlobCreateOptions = {}
   ): Promise<Models.AppendBlobCreateResponse> {
     const { span, spanOptions } = createSpan("AppendBlobClient-create", options.spanOptions);
-    options.accessConditions = options.accessConditions || {};
+    options.conditions = options.conditions || {};
     try {
       ensureCpkIfSpecified(options.customerProvidedKey, this.isHttps);
 
       return this.appendBlobContext.create(0, {
         abortSignal: options.abortSignal,
         blobHTTPHeaders: options.blobHTTPHeaders,
-        leaseAccessConditions: options.accessConditions.leaseAccessConditions,
+        leaseAccessConditions: options.conditions,
         metadata: options.metadata,
-        modifiedAccessConditions: options.accessConditions.modifiedAccessConditions,
+        modifiedAccessConditions: options.conditions,
         cpkInfo: options.customerProvidedKey,
         spanOptions
       });
@@ -426,15 +426,15 @@ export class AppendBlobClient extends BlobClient {
     options: AppendBlobAppendBlockOptions = {}
   ): Promise<Models.AppendBlobAppendBlockResponse> {
     const { span, spanOptions } = createSpan("AppendBlobClient-appendBlock", options.spanOptions);
-    options.accessConditions = options.accessConditions || {};
+    options.conditions = options.conditions || {};
     try {
       ensureCpkIfSpecified(options.customerProvidedKey, this.isHttps);
 
       return this.appendBlobContext.appendBlock(body, contentLength, {
         abortSignal: options.abortSignal,
-        appendPositionAccessConditions: options.accessConditions.appendPositionAccessConditions,
-        leaseAccessConditions: options.accessConditions.leaseAccessConditions,
-        modifiedAccessConditions: options.accessConditions.modifiedAccessConditions,
+        appendPositionAccessConditions: options.conditions,
+        leaseAccessConditions: options.conditions,
+        modifiedAccessConditions: options.conditions,
         onUploadProgress: options.onProgress,
         transactionalContentMD5: options.transactionalContentMD5,
         transactionalContentCrc64: options.transactionalContentCrc64,
@@ -478,8 +478,8 @@ export class AppendBlobClient extends BlobClient {
       "AppendBlobClient-appendBlockFromURL",
       options.spanOptions
     );
-    options.accessConditions = options.accessConditions || {};
-    options.sourceModifiedAccessConditions = options.sourceModifiedAccessConditions || {};
+    options.conditions = options.conditions || {};
+    options.sourceConditions = options.sourceConditions || {};
     try {
       ensureCpkIfSpecified(options.customerProvidedKey, this.isHttps);
 
@@ -488,14 +488,14 @@ export class AppendBlobClient extends BlobClient {
         sourceRange: rangeToString({ offset: sourceOffset, count }),
         sourceContentMD5: options.sourceContentMD5,
         sourceContentCrc64: options.sourceContentCrc64,
-        leaseAccessConditions: options.accessConditions.leaseAccessConditions,
-        appendPositionAccessConditions: options.accessConditions.appendPositionAccessConditions,
-        modifiedAccessConditions: options.accessConditions.modifiedAccessConditions,
+        leaseAccessConditions: options.conditions,
+        appendPositionAccessConditions: options.conditions,
+        modifiedAccessConditions: options.conditions,
         sourceModifiedAccessConditions: {
-          sourceIfMatch: options.sourceModifiedAccessConditions.ifMatch,
-          sourceIfModifiedSince: options.sourceModifiedAccessConditions.ifModifiedSince,
-          sourceIfNoneMatch: options.sourceModifiedAccessConditions.ifNoneMatch,
-          sourceIfUnmodifiedSince: options.sourceModifiedAccessConditions.ifUnmodifiedSince
+          sourceIfMatch: options.sourceConditions.ifMatch,
+          sourceIfModifiedSince: options.sourceConditions.ifModifiedSince,
+          sourceIfNoneMatch: options.sourceConditions.ifNoneMatch,
+          sourceIfUnmodifiedSince: options.sourceConditions.ifUnmodifiedSince
         },
         cpkInfo: options.customerProvidedKey,
         spanOptions