Split libraries into independent Gradle projects

.github/workflows/test-android.yaml

@@ -44,7 +44,11 @@ jobs:
         run: rustup target add x86_64-linux-android aarch64-linux-android armv7-linux-androideabi
 
       - name: Build bdk-android library
-        run: ./gradlew :android:buildAndroidLib
+        run: |
+          cd bdk-android
+          ./gradlew buildAndroidLib
 
       - name: Run Android tests
-        run: ./gradlew :android:test --console=rich
+        run: |
+          cd bdk-android
+          ./gradlew test --console=rich

.github/workflows/test-jvm.yaml

@@ -29,7 +29,11 @@ jobs:
           java-version: 11
 
       - name: Build bdk-jvm library
-        run: ./gradlew :jvm:buildJvmLib
+        run: |
+          cd bdk-jvm
+          ./gradlew buildJvmLib
 
       - name: Run JVM tests
-        run: ./gradlew :jvm:test --console=rich
+        run: |
+          cd bdk-jvm
+          ./gradlew test --console=rich