[WebSites] Fixes to HTTP response codes, missing enum properties

[nking-1]

Description

This change adds some missing HTTP response codes for APIs required by the PowerShell project. It also adds missing SKUs to the AppServicePlans. It is needed to get our new PowerShell commands working. Most of the files have been modified with a small comment due to an Autorest update.

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• I have read the contribution guidelines.
• The pull request does not introduce breaking changes.

General Guidelines

• Title of the pull request is clear and informative.
• There are a small number of commits, each of which have an informative message. This means that previously merged commits do not appear in the history of the PR. For more information on cleaning up the commits in your PR, see this page.

Testing Guidelines

• Pull request includes test coverage for the included changes.

SDK Generation Guidelines

• If an SDK is being regenerated based on a new swagger spec, a link to the pull request containing these swagger spec changes has been included above.
• The generate.cmd file for the SDK has been updated with the version of AutoRest, as well as the commitid of your swagger spec or link to the swagger spec, used to generate the code.
• The *.csproj and AssemblyInfo.cs files have been updated with the new version of the SDK.

[nking-1]

@shahabhijeet Can you please review this PR?

[markcowl]

The generated code looks fine, but:

(1) Please include the metadata file here:https://github.com/Azure/azure-sdk-for-net/tree/psSdkJson6/src/SDKs/_metadata which is automatically generated by AutoRest
(2) Please update the csproj with release notes and a version update
(3) Please include tests

[nking-1]

(1) I can't find this metadata file anywhere after generating the code with AuotRest. I'm running "autorest --csharp" from azure-rest-api-specs/specification/web/resource-manager with autorest 2.0.4166. The only output I see is C# code. Any advice on how I can get the metadata?
(3) I'll include a test for the PremiumV2 SKU that was added, but other updates in the PR are just metadata changes. Recorded tests should still be passing. Hopefully that's good enough for now.

[shahabhijeet]

@Nking92 if you do not have a generate.cmd under you sdk folder, you should create one by modelling it from other RPs.
Let me know if you cannot find the generate.cmd file which will generate your SDK

[nking-1]

Got it, I was trying to directly use autorest instead of using the generate.cmd script. I regenerated with that script in the latest commit. It's a large number of changes once again, but it is working fine with our PowerShell project, which is good news.

[nking-1]

I opened an issue to write more tests at #3844. Our API is so large that I would not be able to test it all without a huge time investment. I realize tests important, but we are also under pressure to get an SDK update published, which we can use for PowerShell, which has some broken commands that are causing pain for customers.