Add tests for cli

[varmar05]

Example test (project create) for testing cli commands.

[coveralls]

Pull Request Test Coverage Report for Build 16651130116

Details

• 314 of 326 (96.32%) changed or added relevant lines in 7 files are covered.
• 4 unchanged lines in 1 file lost coverage.
• Overall coverage increased (+2.4%) to 94.107%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
server/mergin/sync/commands.py	28	30	93.33%
server/mergin/tests/test_cli.py	172	174	98.85%
server/mergin/commands.py	102	110	92.73%

Files with Coverage Reduction	New Missed Lines	%
server/mergin/tests/test_middleware.py	4	80.0%

Totals
Change from base Build 15999513920:	2.4%
Covered Lines:	7442
Relevant Lines:	7908

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💛 - Coveralls

[MarcelGeo]

I think we could add following framework to our private repo too. To unify it.

[MarcelGeo]

@harminius would you provide tests for more commands?

[varmar05]

Looks good to me.