Fixes packaging for current p4a develop branch

[misl6]

This PR fixes packaging for current p4a develop branch.

Needed due to changes in p4a PR kivy/python-for-android#1986.

[AndreMiras]

Looking good thanks! I'll test it today and merge if it works OK

[AndreMiras]

I confirm that fixes it. Before fix the end of buildozer android debug log was:

[INFO]:    # Your distribution was created successfully, exiting.
[INFO]:    Dist can be found at (for now) /home/andre/workspace/QrScan/.buildozer/android/platform/build/dists/qrscan__armeabi-v7a
# Build the application #1                                                       
# Copy application source from /home/andre/workspace/QrScan/src                 
# Create directory /home/andre/workspace/QrScan/.buildozer/android/app                                                                                                                                            
# Copy /home/andre/workspace/QrScan/src/main.py
# Create directory /home/andre/workspace/QrScan/.buildozer/android/app/qrscan
# Copy /home/andre/workspace/QrScan/src/qrscan/__init__.py                
# Copy /home/andre/workspace/QrScan/src/qrscan/version.py                     
# Copy /home/andre/workspace/QrScan/src/qrscan/main.py                    
# Copy /home/andre/workspace/QrScan/src/qrscan/main.kv
# Package the application                                                      
# Captured version: 2019.0911   
Traceback (most recent call last):
  File "/home/andre/.local/bin/buildozer", line 10, in <module>
    sys.exit(main())                                                                                                                                                                                                                                                            
  File "/home/andre/.local/lib/python3.6/site-packages/buildozer/scripts/client.py", line 13, in main                                                                                      
    Buildozer().run_command(sys.argv[1:])                                        
  File "/home/andre/.local/lib/python3.6/site-packages/buildozer/__init__.py", line 1062, in run_command
    self.target.run_commands(args)                                
  File "/home/andre/.local/lib/python3.6/site-packages/buildozer/target.py", line 92, in run_commands
    func(args)                                                     
  File "/home/andre/.local/lib/python3.6/site-packages/buildozer/target.py", line 104, in cmd_debug
    self.buildozer.build()                         
  File "/home/andre/.local/lib/python3.6/site-packages/buildozer/__init__.py", line 222, in build
    self.target.build_package()                             
  File "/home/andre/.local/lib/python3.6/site-packages/buildozer/targets/android.py", line 978, in build_package
    self._update_libraries_references(dist_dir)
  File "/home/andre/.local/lib/python3.6/site-packages/buildozer/targets/android.py", line 1191, in _update_libraries_references
    with io.open(project_fn, 'w', encoding='utf-8') as fd:                                       
FileNotFoundError: [Errno 2] No such file or directory: '/home/andre/workspace/QrScan/.buildozer/android/platform/build/dists/qrscan/project.properties'

I've tried the fix with pip3 install --user --upgrade https://github.com/misl6/buildozer/archive/fix-dist-dir.zip and starting a clean build rm -rf .buildozer/
Then I could produce the APK with buildozer android debug, end log was:

[INFO]:    Selecting java build tool:
[INFO]:    Detected highest available build tools version to be 29.0.2
[INFO]:        Building with gradle, as gradle executable is present
[DEBUG]:   -> running gradlew assembleDebug
[DEBUG]:
[DEBUG]:        > Task :compileDebugJavaWithJavac 
[DEBUG]:        Note: Some input files use or override a deprecated API.
[DEBUG]:        Note: Recompile with -Xlint:deprecation for details.
[DEBUG]:        Note: Some input files use unchecked or unsafe operations.
[DEBUG]:        Note: Recompile with -Xlint:unchecked for details.
[DEBUG]:
[DEBUG]:
[DEBUG]:        BUILD SUCCESSFUL in 3s
[DEBUG]:        27 actionable tasks: 27 executed

[INFO]:    <- directory context /home/andre/workspace/QrScan/.buildozer/android/platform/python-for-android
[INFO]:    # Copying APK to current directory
[INFO]:    # APK filename not found in build output. Guessing...
[INFO]:    # Found APK file: /home/andre/workspace/QrScan/.buildozer/android/platform/build-armeabi-v7a/dists/qrscan__armeabi-v7a/build/outputs/apk/debug/qrscan__armeabi-v7a-debug.apk
[INFO]:    # Add version number to APK
[INFO]:    # APK renamed to qrscan__armeabi-v7a-debug-2019.0911-.apk
[DEBUG]:   -> running cp /home/andre/workspace/QrScan/.buildozer/android/platform/build-armeabi-v7a/dists/qrscan__armeabi-v7a/build/outputs/apk/debug/qrscan__armeabi-v7a-debug.apk qrscan__armeabi-v7a-debug-2019.0911-.apk
WARNING: Received a --sdk argument, but this argument is deprecated and does nothing.
No compiled python is present to zip, skipping.
No setup.py/pyproject.toml used, copying full private data into .apk.
Applying Java source code patches...
Applying patch: src/patches/SDLActivity.java.patch
# Android packaging done!
# APK qrscan-2019.0911-armeabi-v7a-debug.apk available in the bin directory