Use coverallsapp/github-action@master in CI.

Author: gkellogg

.github/workflows/ci.yml

@@ -32,7 +32,7 @@ jobs:
       - name: Run tests
         run: ruby --version; bundle exec rspec spec || $ALLOW_FAILURES
       - name: Coveralls GitHub Action
-        uses: coverallsapp/github-action@v1.1.3
+        uses: coverallsapp/github-action@master
         if: "matrix.ruby == '3.0'"
         with:
           github-token: ${{ secrets.GITHUB_TOKEN }}