[test] add --add-opens for sun.security.krb5 to silence reflective-access warning (#6895)

Author: plusplusjiajia

pom.xml

@@ -163,6 +163,7 @@ under the License.
             --add-opens=java.base/sun.nio.cs=ALL-UNNAMED
             --add-opens=java.base/sun.security.action=ALL-UNNAMED
             --add-opens=java.base/sun.util.calendar=ALL-UNNAMED
+            --add-opens=java.security.jgss/sun.security.krb5=ALL-UNNAMED
             -Djdk.reflect.useDirectMethodHandle=false
             -Dio.netty.tryReflectionSetAccessible=true
         </extraJavaTestArgs>