Added wrappers for os.statvfs() and os.path.ismount()

[mdevaev]

Subj. And if it doesn't bother you, I would appreciate it if you would release a minor release with this change, I need it for the upstream of my distro.

[Tinche]

Great, can you add a few tests too?

[Tinche]

And a changelog entry.

[codecov-commenter]

Codecov Report

Patch coverage: 100.00% and project coverage change: +0.05% :tada:

Comparison is base (2e40fc4) 90.98% compared to head (4ad14b0) 91.04%. Report is 11 commits behind head on main.

:exclamation: Current head 4ad14b0 differs from pull request most recent head 2e945ba. Consider uploading reports for the commit 2e945ba to get more accurate results

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Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #162 +/- ## ========================================== + Coverage 90.98% 91.04% +0.05% ========================================== Files 10 10 Lines 344 346 +2 ========================================== + Hits 313 315 +2 Misses 31 31 ``` | [Files Changed](https://app.codecov.io/gh/Tinche/aiofiles/pull/162?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Tin+Tvrtkovi%C4%87) | Coverage Δ | | |---|---|---| | [src/aiofiles/os.py](https://app.codecov.io/gh/Tinche/aiofiles/pull/162?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Tin+Tvrtkovi%C4%87#diff-c3JjL2Fpb2ZpbGVzL29zLnB5) | `100.00% <100.00%> (ø)` | | | [src/aiofiles/ospath.py](https://app.codecov.io/gh/Tinche/aiofiles/pull/162?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Tin+Tvrtkovi%C4%87#diff-c3JjL2Fpb2ZpbGVzL29zcGF0aC5weQ==) | `100.00% <100.00%> (ø)` | |

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[mdevaev]

Great, can you add a few tests too?

Sure. Pushed.

[Tinche]

@mdevaev Great, sorry for the delay. We just need a small doc update so folks know it was added in this version (so, the Changelog section) and so folks know it exists (around https://github.com/Tinche/aiofiles/blob/564b11edd2b384d7bf262ac14df340405acd2f14/README.md?plain=1#L94). And I push the merge button ;)

[mdevaev]

@Tinche It's done, please take a look. I've also rebased it and resolved conflicts.

[Tinche]

Thanks!