Add check_path()

[WenjieDu]

What does this PR do?

1. adding tsdb.utils.file.check_path();

Before submitting

• This PR is made to fix a typo or improve the docs (you can dismiss the other checks if this is the case).
• Was this discussed/approved via a GitHub issue? Please add a link to it if that's the case.
• I have commented my code, particularly in hard-to-understand areas.
• I have written necessary tests and already run them locally.

[coveralls]

Pull Request Test Coverage Report for Build 9708255707

Details

• 22 of 25 (88.0%) changed or added relevant lines in 1 file are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage decreased (-0.02%) to 82.939%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
tsdb/utils/file.py	22	25	88.0%

Files with Coverage Reduction	New Missed Lines	%
tsdb/utils/file.py	1	74.16%

Totals
Change from base Build 9707011964:	-0.02%
Covered Lines:	491
Relevant Lines:	592

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💛 - Coveralls