Fix Android build: set absolute path for keystore file

Author: acronomi-konomi

.github/workflows/build-apps.yml

@@ -41,7 +41,7 @@ jobs:
       run: |
         cd android
         ./gradlew assembleRelease \
-          -Pandroid.injected.signing.store.file=my-release-key.jks \
+          -Pandroid.injected.signing.store.file=$GITHUB_WORKSPACE/android/app/my-release-key.jks \
           -Pandroid.injected.signing.store.password=${{ secrets.KEYSTORE_PASSWORD }} \
           -Pandroid.injected.signing.key.alias=${{ secrets.KEY_ALIAS }} \
           -Pandroid.injected.signing.key.password=${{ secrets.KEYSTORE_PASSWORD }}