Add Python 3.12 to test matrix

[ktbyers]

@ogenstad I would probably try rolling nornir-napalm to 0.5.0 (since your error seems related to outdated ncclient which is possibly being caused by older nornir-napalm):

https://github.com/nornir-automation/nornir/blob/main/pyproject.toml#L46

And it should be updated anyways.

[ogenstad]

@ktbyers, thanks. Looks like it got a bit further but hit the next problem. Might be that we just need to upgrade nbval, I'll try to return to it a bit later.

[coveralls]

Pull Request Test Coverage Report for Build 9890392497

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 56.677%

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Totals
Change from base Build 9886686772:	0.0%
Covered Lines:	539
Relevant Lines:	951

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💛 - Coveralls

[ktbyers]

LGTM