Add a test case to indicate shebang including invalid utf-8 char

[u5surf]

To fixes #28, cover the test for
https://codecov.io/gh/brettcannon/python-launcher/src/master/src/cli.rs#L148

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• UNDERSTOOD: Brett is using this project to teach himself Rust, so I will
  not feel offended if he chooses not to accept this PR in order for him to learn how to do
  something on his own. (PRs to do something more idiomatically are very much appreciated,
  though.)

[codecov]

Codecov Report

Merging #29 into master will increase coverage by 0.32%.
The diff coverage is 100.00%.

@@             Coverage Diff             @@
##           master       #29      +/-   ##
===========================================
+ Coverage   99.67%   100.00%   +0.32%     
===========================================
  Files           2         2              
  Lines         312       312              
===========================================
+ Hits          311       312       +1     
+ Misses          1         0       -1     

Impacted Files	Coverage Δ
src/cli.rs	100.00% <100.00%> (+0.67%)	⬆️
src/lib.rs	100.00% <0.00%> (ø)

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[brettcannon]

@u5surf I just wanted to say thanks for the PR and that I am not purposefully ignoring it; just been too busy to work on this project lately. But I will eventually review it.

[brettcannon]

Thanks, @u5surf !

[zachgates]

Hey there.

I was in the process of reading through the source code (trying to assimilate some Rust literacy), and I happened upon a typo in /src/cli.rs. I considered opening a new issue, but ultimately decided that the de facto label, bug, was not an apt descriptor. So, I dug a bit deeper — looking for someone to git blame — and wound up here.

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The aggregate changes contained in this PR were merged into main at 2361a7f from u5surf:issue-28.

    #[test_case(&[0x23, 0x21, 0xc0, 0xaf] => None ; "invalid UTF-8")]
    fn parse_python_sheban_include_invalid_bytes_tests(
        mut shebang: &[u8],
    ) -> Option<RequestedVersion> {
        parse_python_shebang(&mut shebang)
    }

The word-perfect function name is parse_python_shebang_include_invalid_bytes_tests — as sheban becomes shebang. Extrapolating from your commit history, I presume that a supplementary commit (amending this functionally insignificant typo) would be the normative solution.

I would be happy to make the small contribution myself; however, naturally, you can do whatever you like.

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I would also like to extend my thanks to you for everything you have done here, across the board. Speaking as someone almost totally unfamiliar to Rust, I've gleaned a surprising amount of practical knowledge here — be it idiomatic or not, which I'm sure will increase with additional read-throughs. And, lastly: I'm glad there is finally this promising py port! I'm surprised we've gone this far down the road without one; it's only logical to have a cross-platform solution!

[brettcannon]

@zachgates if you want the contribution, feel free to open a PR, but I can also just make the fix in-place very quickly.

And glad you're getting something (hopefully good) out of the code base!