Adding auto delete workflow for backport branches

[VachaShah]

Signed-off-by: Vacha Shah vachshah@amazon.com

Description

Workflow to automatically delete the branches created by the backport action of type backport/*.

This PR needs to be backported to release branches so that the auto delete runs on backport PRs created for those branches.

Issues Resolved

[List any issues this PR will resolve]

Check List

• Commits are signed per the DCO using --signoff

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.
For more information on following Developer Certificate of Origin and signing off your commits, please check here.

[codecov-commenter]

Codecov Report

Merging #176 (760185c) into main (deae554) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #176   +/-   ##
=======================================
  Coverage   43.87%   43.87%           
=======================================
  Files         156      156           
  Lines        5181     5181           
  Branches      953      953           
=======================================
  Hits         2273     2273           
  Misses       2690     2690           
  Partials      218      218           

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update deae554...760185c. Read the comment docs.

[opensearch-trigger-bot]

The backport to 1.x failed:

The process '/usr/bin/git' failed with exit code 1

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-1.x 1.x
# Navigate to the new working tree
cd .worktrees/backport-1.x
# Create a new branch
git switch --create backport/backport-176-to-1.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 c9aeecde2f0f9cff0d8b8e9ebea77c5a1c861e72
# Push it to GitHub
git push --set-upstream origin backport/backport-176-to-1.x
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-1.x

Then, create a pull request where the base branch is 1.x and the compare/head branch is backport/backport-176-to-1.x.