The tag help tests were failing under test runners like `stestr` because
the program name in the `usage:` string was unpredictable.
This commit hardcodes `prog='run.py'` in the ArgumentParser used for
testing, ensuring the help output is consistent and independent of the
test execution environment.
Change-Id: I813c266b9523e5f1234885da7b6ded41e02ad3b6
Signed-off-by: Myles Penner <myles.penner@canonical.com>
Closes-bug: 2138684