deps: Update guava version in grpc-gcp

Author: lqiu96

grpc-gcp-java/pom.xml

@@ -67,7 +67,7 @@
     <error-prone-annotations.version>2.48.0</error-prone-annotations.version>
     <google-http-client.version>2.2.0</google-http-client.version>
     <gson.version>2.13.2</gson.version>
-    <guava.version>33.5.0-jre</guava.version>
+    <guava.version>33.6.0-jre</guava.version>
     <protobuf.version>4.33.2</protobuf.version>
     <grpc.version>1.81.0</grpc.version>
     <jsr305.version>3.0.2</jsr305.version>