exploit-apk not working on windows

[DarkSurferZA]

qark --apk app-debug.apk --report-type html --exploit-apk --sdk-path apkpathgoeshere
....
Finish writing report to c:\programdata\miniconda3\envs\qark\lib\site-packages\qark\report\report.html ...
Building exploit APK...
Error running command %s
Traceback (most recent call last):
  File "c:\programdata\miniconda3\envs\qark\lib\site-packages\qark\apk_builder.py", line 115, in _build_apk
    subprocess.call(shlex.split(command))
  File "c:\programdata\miniconda3\envs\qark\lib\subprocess.py", line 172, in call
    return Popen(*popenargs, **kwargs).wait()
  File "c:\programdata\miniconda3\envs\qark\lib\subprocess.py", line 394, in __init__
    errread, errwrite)
  File "c:\programdata\miniconda3\envs\qark\lib\subprocess.py", line 644, in _execute_child
    startupinfo)
WindowsError: [Error 193] %1 is not a valid Win32 application
Traceback (most recent call last):
  File "c:\programdata\miniconda3\envs\qark\lib\runpy.py", line 174, in _run_module_as_main
    "__main__", fname, loader, pkg_name)
  File "c:\programdata\miniconda3\envs\qark\lib\runpy.py", line 72, in _run_code
    exec code in run_globals
  File "C:\ProgramData\Miniconda3\envs\qark\Scripts\qark.exe\__main__.py", line 7, in <module>
  File "c:\programdata\miniconda3\envs\qark\lib\site-packages\click\core.py", line 829, in __call__
    return self.main(*args, **kwargs)
  File "c:\programdata\miniconda3\envs\qark\lib\site-packages\click\core.py", line 782, in main
    rv = self.invoke(ctx)
  File "c:\programdata\miniconda3\envs\qark\lib\site-packages\click\core.py", line 1066, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "c:\programdata\miniconda3\envs\qark\lib\site-packages\click\core.py", line 610, in invoke
    return callback(*args, **kwargs)
  File "c:\programdata\miniconda3\envs\qark\lib\site-packages\click\decorators.py", line 21, in new_func
    return f(get_current_context(), *args, **kwargs)
  File "c:\programdata\miniconda3\envs\qark\lib\site-packages\qark\qark.py", line 102, in cli
    exploit_builder.build()
  File "c:\programdata\miniconda3\envs\qark\lib\site-packages\qark\apk_builder.py", line 76, in build
    self._build_apk()
  File "c:\programdata\miniconda3\envs\qark\lib\site-packages\qark\apk_builder.py", line 116, in _build_apk
    subprocess.call(shlex.split(command))
  File "c:\programdata\miniconda3\envs\qark\lib\subprocess.py", line 172, in call
    return Popen(*popenargs, **kwargs).wait()
  File "c:\programdata\miniconda3\envs\qark\lib\subprocess.py", line 394, in __init__
    errread, errwrite)
  File "c:\programdata\miniconda3\envs\qark\lib\subprocess.py", line 644, in _execute_child
    startupinfo)
WindowsError: [Error 193] %1 is not a valid Win32 application

Problem seems to be in this file: c:\programdata\miniconda3\envs\qark\lib\site-packages\qark\apk_builder.py

After inspecting the file, line 115 is attempting to launch ./gradlew. this obviously isnt suitable to Windows environments and would have to be changed to gradlew.bat

Suggested change in the project is to include an if os.name == 'nt': check and then make use of either ./gradlew or gradlew.bat.

Willing to create a pull request, but not sure of other impacts this may have.