deps: update google.core.version to v2.8.28 (#909)

Author: renovate-bot

first-party-dependencies/pom.xml

@@ -63,7 +63,7 @@
     <protobuf.version>3.21.9</protobuf.version>
     <google.api-common.version>2.2.2</google.api-common.version>
     <google.common-protos.version>2.10.0</google.common-protos.version>
-    <google.core.version>2.8.27</google.core.version>
+    <google.core.version>2.8.28</google.core.version>
     <google.auth.version>1.12.1</google.auth.version>
     <google.http-client.version>1.42.3</google.http-client.version>
     <google.oauth-client.version>1.34.1</google.oauth-client.version>