build(java): update renovate config to mark conformance tests as a test commit type (#1199)

Author: kolea2

synthtool/gcp/templates/java_library/renovate.json

@@ -50,7 +50,8 @@
         "^junit:junit",
         "^com.google.truth:truth",
         "^org.mockito:mockito-core",
-        "^org.objenesis:objenesis"
+        "^org.objenesis:objenesis",
+        "^com.google.cloud:google-cloud-conformance-tests"
       ],
       "semanticCommitType": "test",
       "semanticCommitScope": "deps"