Fix for specifying cpy-version when installing

[RoscoP]

Scope

Fixing an exception issue when using circup, and specifying --cpy-version. This makes changes to the main() and version_override values passed to the backends. Previously this value was set to a string, but usage of get_circuitpython_version() returned a tuple.

Behavior

Previously, calling circup --path . --cpy-version '10.0.3' --board-id adafruit_qtpy_esp32s2 install adafruit-circuitpython-asyncio caused an exception:

  File "...\Lib\site-packages\circup\bundle.py", line 61, in lib_dir
    self.basename.format(platform=PLATFORMS[platform], tag=tag),
                                  ~~~~~~~~~^^^^^^^^^^
KeyError: '1mpy'

This was due to this line:

# DiskBackEnd.install_module_mpy()
...
major_version = self.get_circuitpython_version()[0].split(".")[0]

Requiring the return value to be a tuple, the first entry to be a semver. This fix resolves this.

[dunkmann00]

I think this should be an and if we go by the cli help description for these flags.

[dunkmann00]

This becomes not necessary with the improvement you made. If you want you could make this just cpy_version, board_id = ctx.obj["backend"].get_circuitpython_version()

[dunkmann00]

Hey nice catch! I'm not a maintainer but have done some work with this repo lately and had a couple of suggestions that I thought I'd share.