GitHub Actions faster!! (#7268)

Use new meshtastic/gh-action-firmware Action

Co-authored-by: Ben Meadors <benmmeadors@gmail.com>

.github/workflows/main_matrix.yml

@@ -135,6 +135,7 @@ jobs:
       board: ${{ matrix.board }}
 
   build-debian-src:
+    if: github.repository == 'meshtastic/firmware'
     uses: ./.github/workflows/build_debian_src.yml
     with:
       series: UNRELEASED
@@ -425,7 +426,7 @@ jobs:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
   publish-firmware:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     if: ${{ github.event_name == 'workflow_dispatch' }}
     needs: [release-firmware]
     env: