[BUG] Files input doesn't work when running with act

[stevehipwell]

Is there an existing issue for this?

• I have searched the existing issues

Does this issue exist in the latest version?

• I'm using the latest release

Describe the bug?

When running this action with act (medium image) and providing a files input, the full list of modified files is returned rather than the a filtered list.

To Reproduce

1. Add action to repo as configured below
2. Add multiple changed files in commit, but only 1 with a .yaml extension
3. Run action locally with act

name: Test

on:
  push:

jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout
        uses: actions/checkout@v2
        with:
          fetch-depth: 0

      - name: Get changes
        id: changes
        uses: tj-actions/changed-files@v11.6
        with:
          files: \.yaml$

      - name: Show changes
        shell: bash
        run: |
          set -euo pipefail

          for file in ${{ steps.changes.outputs.all_modified_files }}
          do
            echo "${file}"
          done

What OS are you seeing the problem on?

ubuntu-latest or ubuntu-20.04

Expected behavior?

The same output should happen with act and on GitHub.

Relevant log output

No response

Anything else?

No response

Code of Conduct

• I agree to follow this project's Code of Conduct

[github-actions]

Thanks for reporting this issue.

[jackton1]

After testing this locally I can confirm that this is a problem with act, and I created a related issue.