This is a follow-up for #1160 and #1168.
Addresses the following:
- grows `buildozer/targets/ios.py` target coverage from 24% to 56%
- fixes `AttributeError` on `TargetIos` error call
Next up should be improving:
- code signing process (toggle off not fully integrated)
- actual deployment (not yet tested)
- further increase `buildozer/targets/ios.py` test coverage
- basic ios target test
- refactors existing android test for code sharing
- changes `call_build_package()` to simple function
Grows `buildozer/targets/ios.py` coverage from 11% to 24%.
This setups the canvas for more tests to come later.
