ci: Install chromium from PPA

Vhs installs chromium for testing, but it may slow downs things a bit if
done during tests (as it may be repeated), while doing it once here
avoids such issue

.github/workflows/qa.yaml

@@ -152,6 +152,11 @@ jobs:
             sudo apt remove -y ubuntu-dev-tools
             sudo apt autoremove -y
           fi
+      - name: Install Chromium from PPA # It's used by vhs, speeds up tests.
+        run: |
+          set -eu
+          sudo add-apt-repository -y ppa:savoury1/chromium
+          sudo apt install -y chromium
       - uses: actions/checkout@v4
       - uses: actions/setup-go@v5
         with: