Fix the regular expression for the commit queue label access

Change-Id: Ic0690f1364090a11ea16679fac323e4070596bd9
Reviewed-on: https://go-review.googlesource.com/c/All-Projects/+/469995
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>