ci: Add checking for building OpenXR loader with Gradle

Signed-off-by: utzcoz <utzcoz@outlook.com>

Author: utzcoz

.github/workflows/android-OpenXR-loader.yml

@@ -0,0 +1,30 @@
+# Copyright 2022, Collabora, Ltd.
+# SPDX-License-Identifier: CC0-1.0
+
+name: OpenXR Loader for Android - Check
+on:
+  pull_request:
+
+jobs:
+  build-loader:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Install ninja-build tool
+        uses: seanmiddleditch/gha-setup-ninja@v3
+      - name: set up JDK 11
+        uses: actions/setup-java@v2
+        with:
+          java-version: "11"
+          distribution: "adopt"
+          cache: gradle
+
+      - name: Build OpenXR Loader with Gradle for Android
+        run: |
+          cd src/loader
+          ./gradlew build
+      - name: Upload OpenXR Loader for Android
+        uses: actions/upload-artifact@v2
+        with:
+          name: OpenXR Loader for Android
+          path: src/loader/build/outputs/aar/