Improved the naming convention for the dummy AAB file.

* The new naming format for the dummy AAB file will be something like `org.kiwix.kiwixcustomAPPNAME_dummy.aab`, where 'APPNAME' will be replaced with the actual app name.

.github/workflows/publish.yml

@@ -89,10 +89,12 @@ jobs:
         id: bundle-path
         run: |
           BUNDLE_PATH="kiwix-android/custom/build/outputs/bundle/${TAG}Release/*${TAG}*.aab"
+          FILE_NAME="org.kiwix.kiwixcustom${TAG}_dummy.aab"
           echo "::set-output name=bundle_path::$BUNDLE_PATH"    
+          echo "::set-output name=file_name::$FILE_NAME"    
 
       - name: Upload APK as an artifact
         uses: actions/upload-artifact@v2
         with:
-          name: "Dummy Bundle for play store"
+          name: ${{ steps.bundle-path.outputs.file_name }}
           path: ${{ steps.bundle-path.outputs.bundle_path }}