Just use `std::filesystem`

[emlowe]

We require C++17 where std::filesystem is standard and we don't support some of the older systems (like Mojave) anymore where we need to use some other things like gulrak or experimental

[coveralls-official[bot]]

Pull Request Test Coverage Report for Build 10816320137

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 79.028%

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Totals
Change from base Build 10691731730:	0.0%
Covered Lines:	3497
Relevant Lines:	4425

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💛 - Coveralls