try ffmpeg downloading action

.github/workflows/rust.yml

@@ -14,6 +14,14 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v3
+    - uses: FedericoCarboni/setup-ffmpeg@v3
+      id: setup-ffmpeg
+      with:
+        ffmpeg-version: "8.0"
+        linking-type: static
+        # As of version 3 of this action, builds are no longer downloaded from GitHub
+        # except on Windows: https://github.com/GyanD/codexffmpeg/releases.
+        github-token: ${{ github.server_url == 'https://github.com' && github.token || '' }}
     - name: Rust Cache
       uses: Swatinem/rust-cache@v2.7.7
       with: