fix(snippet-bot): ignore 403 error as well (#1111)
fix(snippet-bot): ignore 403 error as well (#1111)

fixes #1108 
fixes #1110

At least, this will avoid the bot from dying.

googleapis/repo-automation-bots,googleapis/repo-automation-bots,googleapis/repo-automation-bots,googleapis/repo-automation-bots,googleapis/repo-automation-bots