changed comment text

Author: gkevinzheng

google/cloud/bigtable_admin_v2/utils/__init__.py

@@ -13,6 +13,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
-# This directory is for inserting specifically the oneof_message module
-# into files in the autogenerated types directory without causing ImportErrors
-# due to circular imports. For most other use cases, use overlay/types.
+# This directory is a directory for handwritten code, made for inserting
+# specifically the oneof_message module into files in the autogenerated
+# types directory without causing ImportErrors due to circular imports.
+# For other use cases, use the overlay submodule.