chore: regenerate README (#401)

This PR was generated using Autosynth. 🌈


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

```
2021-04-09 19:40:17,419 synthtool [DEBUG] > Executing /root/.cache/synthtool/java-scheduler/.github/readme/synth.py.
On branch autosynth-readme
nothing to commit, working tree clean
2021-04-09 19:40:18,735 synthtool [DEBUG] > Wrote metadata to .github/readme/synth.metadata/synth.metadata.

```
</details>

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.github/readme/synth.metadata/synth.metadata

@@ -4,7 +4,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-scheduler.git",
-        "sha": "be2edcf0ad844fb993f51cd3370c7243bd93d213"
+        "sha": "633e4310620e66666b946f28dec6bbfb4d85e802"
       }
     },
     {

README.md

@@ -54,12 +54,12 @@ compile 'com.google.cloud:google-cloud-scheduler'
 ```
 If you are using Gradle without BOM, add this to your dependencies
 ```Groovy
-compile 'com.google.cloud:google-cloud-scheduler:1.23.9'
+compile 'com.google.cloud:google-cloud-scheduler:1.23.10'
 ```
 
 If you are using SBT, add this to your dependencies
 ```Scala
-libraryDependencies += "com.google.cloud" % "google-cloud-scheduler" % "1.23.9"
+libraryDependencies += "com.google.cloud" % "google-cloud-scheduler" % "1.23.10"
 ```
 
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