Remove GenericTypeIndicator in error messages

Author: cherylEnkidu

firebase-firestore/src/main/java/com/google/firebase/firestore/util/CustomClassMapper.java

@@ -249,7 +249,7 @@ private static <T> T deserializeToClass(Object o, Class<T> clazz, DeserializeCon
           context.errorPath,
           "Class "
               + clazz.getName()
-              + " has generic type parameters, please use GenericTypeIndicator instead");
+              + " has generic type parameters");
     } else if (clazz.equals(Object.class)) {
       return (T) o;
     } else if (clazz.isEnum()) {

firebase-firestore/src/test/java/com/google/firebase/firestore/util/MapperTest.java

@@ -1920,7 +1920,7 @@ public void passingInByteTopLevelThrows() {
   public void passingInGenericBeanTopLevelThrows() {
     assertExceptionContains(
         "Class com.google.firebase.firestore.util.MapperTest$GenericBean has generic type "
-            + "parameters, please use GenericTypeIndicator instead",
+            + "parameters",
         () -> deserialize("{'value': 'foo'}", GenericBean.class));
   }