fix: fix typo for path on Windows

[weasdown]

In the ffi sample, fix a typo that prevents the running of the primitives example on Windows.

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[coveralls]

Pull Request Test Coverage Report for Build 16218243466

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 90.909%

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Totals
Change from base Build 14498605564:	0.0%
Covered Lines:	20
Relevant Lines:	22

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💛 - Coveralls