Owner files should have full emails.

The owner file validations is failing because is not using full emails.
This CL is fixing that.

Change-Id: I10b1799f84a06829eee0ab35f73c248e52324054
Reviewed-on: https://flutter-review.googlesource.com/c/recipes/+/4041
Reviewed-by: Keyong Han <keyonghan@google.com>
Commit-Queue: Godofredo Contreras <godofredoc@google.com>