Actions: Use correct key for coveralls per docs

Author: simmsa

.github/workflows/main.yml

@@ -760,5 +760,4 @@ jobs:
         uses: coverallsapp/github-action@v2
         with:
           parallel-finished: true
-        env:
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          github-token: ${{ secrets.GITHUB_TOKEN }}