ci(java): ignore bot users for generate-files-bot (#756)

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Source-Link: googleapis/synthtool@3f67cee

.github/generated-files-bot.yml

@@ -5,3 +5,7 @@ externalManifests:
 - type: json
   file: '.github/readme/synth.metadata/synth.metadata'
   jsonpath: '$.generatedFiles[*]'
+ignoreAuthors:
+- 'renovate-bot'
+- 'yoshi-automation'
+- 'release-please[bot]'

synth.metadata

@@ -4,7 +4,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-spanner.git",
-        "sha": "3b42e9101bc7898be428c3046615df8868ca40c0"
+        "sha": "aa701f5998b17d918e3042b20c73ab9dbbcd4e27"
       }
     },
     {
@@ -19,7 +19,7 @@
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "5d11bd2888c38ce1fb6fa6bf25494a4219a73928"
+        "sha": "3f67ceece7e797a5736a25488aae35405649b90b"
       }
     }
   ],