build(java): update autorelease branch name check (googleapis#345)

This PR was generated using Autosynth. 🌈

Synth log will be available here:
https://source.cloud.google.com/results/invocations/aa15b03c-7629-4b5d-b5c2-a0ea5047610d/targets

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Source-Link: googleapis/synthtool@140ba24

.github/workflows/auto-release.yaml

@@ -17,7 +17,7 @@ jobs:
           }
 
           // only approve PRs like "chore: release <release version>"
-          if ( !context.payload.pull_request.title.startsWith("chore: release") ) {
+          if ( !context.payload.pull_request.title.startsWith("chore(master): release") ) {
             return;
           }
 

synth.metadata

@@ -4,14 +4,14 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-spanner-jdbc.git",
-        "sha": "acf76ee06c49cc2c47825b8654a9a81b7407d24a"
+        "sha": "4daa18d69e2976964e5aae24043ada1fabba04a4"
       }
     },
     {
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "e935c9ecb47da0f2e054f5f1845f7cf7c95fa625"
+        "sha": "140ba24a136c63e7f10a998a63e7898aed63ea7d"
       }
     }
   ],