chore(java): enable generated-files-bot (#288)

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https://source.cloud.google.com/results/invocations/25b2b66f-779b-4484-89b9-09a27306cbca/targets

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Source-Link: googleapis/synthtool@b19b401

Author: yoshi-automation

.github/generated-files-bot.yml

@@ -0,0 +1,7 @@
+externalManifests:
+- type: json
+  file: 'synth.metadata'
+  jsonpath: '$.generatedFiles[*]'
+- type: json
+  file: '.github/readme/synth.metadata/synth.metadata'
+  jsonpath: '$.generatedFiles[*]'

synth.metadata

@@ -4,7 +4,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-tasks.git",
-        "sha": "952328675e1398a73cf240a096978924b1748eb3"
+        "sha": "163fcd1722ade39cab5394260d2ee1c9fbc74966"
       }
     },
     {
@@ -19,7 +19,7 @@
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "5f6ef0ec5501d33c4667885b37a7685a30d41a76"
+        "sha": "b19b401571e77192f8dd38eab5fb2300a0de9324"
       }
     }
   ],
@@ -58,6 +58,7 @@
     ".github/ISSUE_TEMPLATE/feature_request.md",
     ".github/ISSUE_TEMPLATE/support_request.md",
     ".github/PULL_REQUEST_TEMPLATE.md",
+    ".github/generated-files-bot.yml",
     ".github/readme/synth.py",
     ".github/release-please.yml",
     ".github/snippet-bot.yml",