Add Gitea Alpine Package Registry upload step

- Configure upload of Alpine package to personal Gitea package registry
- Add conditional upload step for master branch
- Use curl to upload package with authentication

.github/workflows/build-alpine.yml

@@ -77,4 +77,11 @@ jobs:
         uses: actions/upload-artifact@v3
         with:
           name: cpu-check-alpine
-          path: alpine_build/*.apk 
+          path: alpine_build/*.apk 
+
+      - name: Upload to Gitea Alpine Package Registry
+        if: github.event_name == 'push' && github.ref == 'refs/heads/master'
+        run: |
+          curl --user "eric:df299a6e592a8bd829d018b7816e76d03756408d" \
+               --upload-file alpine_build/cpu-check-${{ env.PKG_VERSION }}-r${{ env.PKG_RELEASE }}.apk \
+               "https://git.ericxliu.me/api/packages/eric/alpine/v3.17/main"