chore: regenerate README (#272)

This PR was generated using Autosynth. 🌈


<details><summary>Log from Synthtool</summary>

```
2021-05-31 18:09:55,390 synthtool [DEBUG] > Executing /root/.cache/synthtool/java-workflows/.github/readme/synth.py.
On branch autosynth-readme
nothing to commit, working tree clean
2021-05-31 18:09:56,748 synthtool [DEBUG] > Wrote metadata to .github/readme/synth.metadata/synth.metadata.

```
</details>

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java-workflows/.github/readme/synth.metadata/synth.metadata

@@ -4,14 +4,14 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-workflows.git",
-        "sha": "91404cef3b9cef16c0e0c1e322a9eda0d4f80b24"
+        "sha": "a815b430327ab91efe0924c0efc85f7e2a81e463"
       }
     },
     {
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "1778de119522ea9c9b18763c2a4577e22a60433c"
+        "sha": "c3e41da0fa256ad7f6b4bc76b9d069dedecdfef4"
       }
     }
   ]

java-workflows/README.md

@@ -17,19 +17,19 @@ If you are using Maven, add this to your pom.xml file:
 <dependency>
   <groupId>com.google.cloud</groupId>
   <artifactId>google-cloud-workflows</artifactId>
-  <version>0.4.2</version>
+  <version>1.0.0</version>
 </dependency>
 
 ```
 
 If you are using Gradle without BOM, add this to your dependencies
 ```Groovy
-compile 'com.google.cloud:google-cloud-workflows:0.4.2'
+compile 'com.google.cloud:google-cloud-workflows:1.0.0'
 ```
 
 If you are using SBT, add this to your dependencies
 ```Scala
-libraryDependencies += "com.google.cloud" % "google-cloud-workflows" % "0.4.2"
+libraryDependencies += "com.google.cloud" % "google-cloud-workflows" % "1.0.0"
 ```
 
 ## Authentication