Quark cannot analyze pivaa.apk when using radare2 as the core library.

[sidra-asa]

Describe the bug
I analyzed the pivaa.apk with radare2 as the core library. The analysis was failed and the message showed that Quark failed to parse the permissions.

To Reproduce
Steps to reproduce the behavior:

$ quark -a pivaa.apk -s --core-library radare2        

    ________                      __
    \_____  \  __ _______ _______|  | __
     /  / \  \|  |  \__  \_  __ \  |/ /
    /   \_/.  \  |  // __ \|  | \/    <
    \_____\ \_/____/(____  /__|  |__|_ \
           \__>          \/           \/ v23.12.1
    
                An Obfuscation-Neglect Android Malware Scoring System
                
  0%|                                                   | 0/211 [00:00<?, ?it/s]
Traceback (most recent call last):
  File "/Users/sasaki/.local/share/virtualenvs/quark-engine-KzHyODU-/bin/quark", line 33, in <module>
    sys.exit(load_entry_point('quark-engine', 'console_scripts', 'quark')())
  File "/Users/sasaki/.local/share/virtualenvs/quark-engine-KzHyODU-/lib/python3.8/site-packages/click/core.py", line 1157, in __call__
    return self.main(*args, **kwargs)
  File "/Users/sasaki/.local/share/virtualenvs/quark-engine-KzHyODU-/lib/python3.8/site-packages/click/core.py", line 1078, in main
    rv = self.invoke(ctx)
  File "/Users/sasaki/.local/share/virtualenvs/quark-engine-KzHyODU-/lib/python3.8/site-packages/click/core.py", line 1434, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/Users/sasaki/.local/share/virtualenvs/quark-engine-KzHyODU-/lib/python3.8/site-packages/click/core.py", line 783, in invoke
    return __callback(*args, **kwargs)
  File "/Users/sasaki/program/python/quark-engine/quark/cli.py", line 334, in entry_point
    data.run(rule_checker)
  File "/Users/sasaki/program/python/quark-engine/quark/core/quark.py", line 458, in run
    elif set(rule_obj.permission).issubset(set(self.apkinfo.permissions)):
  File "/Users/sasaki/.pyenv/versions/3.8.16/lib/python3.8/functools.py", line 967, in __get__
    val = self.func(instance)
  File "/Users/sasaki/program/python/quark-engine/quark/core/r2apkinfo.py", line 220, in permissions
    for elm in axml.get_xml_tree().iter("uses-permission"):
  File "/Users/sasaki/.pyenv/versions/3.8.16/lib/python3.8/xml/etree/ElementTree.py", line 618, in iter
    return self._root.iter(tag)
AttributeError: 'NoneType' object has no attribute 'iter'