build(java): enable blunderbuss for samples (#315)

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Source-Link: googleapis/synthtool@943bb78

.github/blunderbuss.yml

@@ -0,0 +1,7 @@
+# Configuration for the Blunderbuss GitHub app. For more info see
+# https://github.com/googleapis/repo-automation-bots/tree/master/packages/blunderbuss
+assign_prs_by:
+- labels:
+  - samples
+  to:
+  - googleapis/java-samples-reviewers

synth.metadata

@@ -4,7 +4,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-securitycenter.git",
-        "sha": "1c76a98d258da34cb5d41e4084ff6e9684e3fc23"
+        "sha": "9e34b01fc5d8df24a1a6d85bf59acb140a7f81fe"
       }
     },
     {
@@ -35,7 +35,7 @@
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "68742c6016bf0d16948a572633d17955a8737414"
+        "sha": "943bb78606d035001123030067dffcc34f4645f2"
       }
     }
   ],
@@ -74,6 +74,7 @@
     ".github/ISSUE_TEMPLATE/feature_request.md",
     ".github/ISSUE_TEMPLATE/support_request.md",
     ".github/PULL_REQUEST_TEMPLATE.md",
+    ".github/blunderbuss.yml",
     ".github/generated-files-bot.yml",
     ".github/readme/synth.py",
     ".github/release-please.yml",