chore: Test with Protobuf-Java v4.32 [no need to review]

Author: lqiu96

.kokoro/build.sh

@@ -72,6 +72,7 @@ javadoc)
 integration)
     mvn -B ${INTEGRATION_TEST_ARGS} \
       -ntp \
+      -Dprotobuf.version=4.32.0 \
       -Penable-integration-tests \
       -DtrimStackTrace=false \
       -Dclirr.skip=true \
@@ -83,6 +84,7 @@ integration)
 integration-cloud-devel)
     mvn -B ${INTEGRATION_TEST_ARGS} \
       -ntp \
+      -Dprotobuf.version=4.32.0 \
       -Penable-integration-tests \
       -DtrimStackTrace=false \
       -Dclirr.skip=true \
@@ -97,6 +99,7 @@ integration-cloud-devel)
 integration-cloud-staging)
     mvn -B ${INTEGRATION_TEST_ARGS} \
       -ntp \
+      -Dprotobuf.version=4.32.0 \
       -Penable-integration-tests \
       -DtrimStackTrace=false \
       -Dclirr.skip=true \
@@ -110,13 +113,15 @@ integration-cloud-staging)
     ;;
 graalvm)
     # Run Unit and Integration Tests with Native Image.
-    mvn -B ${INTEGRATION_TEST_ARGS} -ntp -Pnative -Penable-integration-tests test "-Dtest=com.google.cloud.spanner.jdbc.it.**"
+    mvn -B ${INTEGRATION_TEST_ARGS} -ntp -Pnative -Penable-integration-tests test "-Dtest=com.google.cloud.spanner.jdbc.it.**" \
+      -Dprotobuf.version=4.32.0
     RETURN_CODE=$?
     ;;
 graalvmA)
     # Run Unit and Integration Tests with Native Image A.
 
-    NATIVE_IMAGE_OPTIONS="--strict-image-heap" mvn -B ${INTEGRATION_TEST_ARGS} -ntp -Pnative -Penable-integration-tests test "-Dtest=com.google.cloud.spanner.jdbc.it.**"
+    NATIVE_IMAGE_OPTIONS="--strict-image-heap" mvn -B ${INTEGRATION_TEST_ARGS} -ntp -Pnative -Penable-integration-tests test "-Dtest=com.google.cloud.spanner.jdbc.it.**" \
+      -Dprotobuf.version=4.32.0
     RETURN_CODE=$?
     ;;
 samples)