Add workflow to publish bdk-jvm (#76)

.github/workflows/test-android.yaml

@@ -0,0 +1,50 @@
+name: Test Android
+on: [push, pull_request]
+
+env:
+  ANDROID_NDK_ROOT: /usr/local/lib/android/sdk/ndk/21.4.7075529
+  # By default the new ubuntu-20.04 images use the following ANDROID_NDK_ROOT
+  # ANDROID_NDK_ROOT: /usr/local/lib/android/sdk/ndk/25.0.8775105
+
+jobs:
+  build:
+    runs-on: ubuntu-20.04
+    steps:
+      - name: Install Android NDK 21.4.7075529
+        run: |
+          ANDROID_ROOT=/usr/local/lib/android
+          ANDROID_SDK_ROOT=${ANDROID_ROOT}/sdk
+          SDKMANAGER=${ANDROID_SDK_ROOT}/cmdline-tools/latest/bin/sdkmanager
+          echo "y" | $SDKMANAGER "ndk;21.4.7075529"
+
+      - name: Check out PR branch
+        uses: actions/checkout@v2
+
+      - name: Update bdk-ffi git submodule
+        run: |
+          git submodule set-url bdk-ffi https://github.com/bitcoindevkit/bdk-ffi.git
+          git submodule update --init bdk-ffi
+
+      - name: cache
+        uses: actions/cache@v2
+        with:
+          path: |
+            ~/.cargo/registry
+            ~/.cargo/git
+            bdk-ffi/target
+          key: ${{ runner.os }}-${{ hashFiles('**/Cargo.toml','**/Cargo.lock') }}
+
+      - name: Set up JDK
+        uses: actions/setup-java@v2
+        with:
+          distribution: temurin
+          java-version: 11
+
+      - name: Install rust android targets
+        run: rustup target add x86_64-linux-android aarch64-linux-android armv7-linux-androideabi
+
+      - name: Build bdk-android library
+        run: ./gradlew :android:buildAndroidLib
+
+      - name: Run Android tests
+        run: ./gradlew :android:test --console=rich