bug: contributors workflow fails with "invalid reference" after merge to main

[udaycodespace]

Description

The update-contributors.yml workflow (added in #11) fails at the
commit step every time a PR is merged into main. Confirmed on the
merge of #11 itself — workflow run failed with:

fatal: invalid reference: feat/issue-10-readme-contributors
Error: Invalid status code: 128

So the automation currently does not work end-to-end. This needs to be
fixed before we can trust it on future contributor merges.

Where to look

• The failure happens in the git-auto-commit-action step, not in the
  Node script.
• Think about what pull_request: closed events actually check out,
  and what branch reference GitHub exposes in that context versus what
  branch we actually want to update.
• Compare what branch name shows up in the failing log versus what
  branch the workflow is supposed to be committing to.

Requirements

• Identify the root cause of the invalid reference error
• Fix the workflow so it reliably targets main regardless of which
  branch the merged PR came from
• Test by simulating a merge (or verifying on the next real contributor
  PR) to confirm the README actually updates on main

Expected outcome

PR merged → workflow runs → commit lands on main → README updates,
no errors in the Actions log.

Tech area

GitHub Actions, YAML, git internals (branch refs on PR-closed events)

[udaycodespace]

Opened #12 — since @Aryanbuha890 built this workflow and already knows the codebase, first shot at claiming this is yours if you want it. Drop your approach in the comments and I'll assign with /assign.
If there's no update in a day or two, I'll open it up for anyone else to claim.

[Aryanbuha890]

/assign , Thank you sir for giving opportunity to contribute in your projects so thank you, kindly assign me this issue

[udaycodespace]

/assign , Thank you sir for giving opportunity to contribute in your projects so thank you, kindly assign me this issue

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