CI: Report formatting issues in CI checks instead of PR reviews

This reports verible formatting issues in CI checks instead of PR
discussions. It may be a question of personal taste, but I see two
advantages:
- Avoid inflated PR discussions (and mails that come with these).
- Allow automated formatting checks *before* opening a PR.

Signed-off-by: Nils Wistoff <[email protected]>

.github/workflows/verible.yml

@@ -3,11 +3,10 @@
 # SPDX-License-Identifier: Apache-2.0
 
 name: Verible
-on:
-  pull_request_target:
+on: [push, pull_request_target]
 
 jobs:
-  format:
+  lint:
     runs-on: ubuntu-latest
     permissions:
       checks: write
@@ -17,7 +16,11 @@ jobs:
       - uses: actions/checkout@v3
         with:
           ref: ${{ github.event.pull_request.head.sha }}
-      - uses: chipsalliance/verible-formatter-action@main
+      - uses: chipsalliance/verible-linter-action@main
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
-          files: 'core/**/*.{v,sv}'
+          paths: 'core/'
+          extensions: |
+            .sv
+            .v
+          reviewdog_reporter: github-check