[roll_to_dev] Use a single push command for commits and tag

b/169389802

Change-Id: I4e3703235a2f2f15d7725a11aa5f5df1f7c2432b
Reviewed-on: https://dart-review.googlesource.com/c/recipes/+/164520
Reviewed-by: William Hesse <whesse@google.com>
Commit-Queue: Alexander Thomas <athom@google.com>
2 files changed