Add sync to board workflow

[pransh15]

Description

Added workflow to add issues to the MDN contributor board.

Motivation

Deliver good-first-issues, accepting PR, and help wanted labelled issues in one board for new contributors.

To fix this issue, add an explicit permissions block to the job or at the workflow root specifying the minimal privileges required. Since there are no obvious write actions in the provided workflow (it checks out code, sets up Node.js, installs a package, and runs a script with a token), the minimal recommended starting point from CodeQL is contents: read. To implement the fix, insert a line 'permissions:\n contents: read\n' under the sync job (i.e., below runs-on: ubuntu-latest) in .github/workflows/mdn-contributor-board.yml. This change restricts the job's GITHUB_TOKEN to read-only access to repository contents, mitigating possible privilege escalation risks.

[caugner]

@pransh15 Is this workflow really necessary?

Two alternatives:

1. Use the "Auto-add to project" workflow in the project (see here).
2. Add a step to the add-issues-to-project workflow in mdn/triagebot (see here).

[caugner]

Note that project workflows can be duplicated:

However, given the number of repos, I would recommend letting triagebot handle it. Triagebot can also maintain "Created at" / "Updated at" columns.