Better version handling for Arduino

[guberti]

This pull request contains three small changes:

• Fix bug allowing microTVM to be used with Arduino version v0.20 and above (see changes to _parse_connected_boards) and adds relevant unit tests.
• Only perform version check when calling build or flash (things that actually require arduino-cli), and adds relevant unit tests.
• Only raise a warning if the arduino-cli version present is below the min version (previously any version other than v0.18 would cause an error).
• Change version comparison to use version.check, like the rest of TVM

[gromero]

@guberti Hi. Thanks for continuing to support Arduino on microTVM :)

I've got some comments inline but overall the change LGTM!

[guberti]

Thanks for the comments @gromero! I've addressed them all, and made a small change to the way we compare versions (we now use version.parse like the rest of TVM).

[gromero]

@guberti Thanks for the fixes and for adding the test for warning_as_error! I agree on using packaging for the version checks. I think I'll use it also for Zephyr :)

I just have one comment - a nit - but won't hold the change on it. Feel free to change it if it makes sense of leave it unchanged.

Finally, out of curiosity, do you know why these Arduino tests are kept in template_project/tests instead of in tests/micro/arduino with the other tests? Should we move everything into tests/micro/arduino?

[guberti]

Finally, out of curiosity, do you know why these Arduino tests are kept in template_project/tests instead of in tests/micro/arduino with the other tests? Should we move everything into tests/micro/arduino?

The original thinking was that unit tests would live in template_project/tests, while integration tests would live in tests/micro/arduino. I don't think this makes very much sense anymore, and I'd be open to moving everything to /tests/micro/arduino. That's probably OOS for this PR, though.

[gromero]

Finally, out of curiosity, do you know why these Arduino tests are kept in template_project/tests instead of in tests/micro/arduino with the other tests? Should we move everything into tests/micro/arduino?

The original thinking was that unit tests would live in template_project/tests, while integration tests would live in tests/micro/arduino. I don't think this makes very much sense anymore, and I'd be open to moving everything to /tests/micro/arduino. That's probably OOS for this PR, though.

Got it! Yeah, that's OOS for this PR, I was just wondering about that organization. 👍