Use preinstalled Android SDK on GitHub Actions runner

Remove the apt dependencies step (buildozer-era packages not needed by
Chaquopy) and the make setup step (SDK, NDK, build-tools, platform-tools
are all preinstalled on ubuntu-latest). The runner provides
ANDROID_SDK_ROOT which the Makefile already respects.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: rtibbles

.github/workflows/build_apk.yml

@@ -130,9 +130,7 @@ jobs:
         name: ${{ inputs.tar-file-name }}
         path: tar
     - name: Install dependencies
-      run: uv pip install --system --extra build -r requirements.txt
-    - name: Ensure that Android SDK dependencies are installed
-      run: make setup
+      run: uv sync --extra build && uv pip install -r requirements.txt
     - name: Build the aab
       if: ${{ inputs.release == true || github.event.inputs.release == 'true' }}
       env: