Refactor platform logic

[Nukesor]

Refacor some statements for conditional compilation for platform specific logic.

Also ignore a flaky test that's triggered in our Apple CI

[codecov-commenter]

Codecov Report

Merging #474 (9c28747) into main (70c1969) will decrease coverage by 0.08%. The diff coverage is n/a.

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@@            Coverage Diff             @@
##             main     #474      +/-   ##
==========================================
- Coverage   79.73%   79.65%   -0.08%     
==========================================
  Files          77       77              
  Lines        5526     5526              
==========================================
- Hits         4406     4402       -4     
- Misses       1120     1124       +4     

Files	Coverage Δ
pueue_lib/src/process_helper/mod.rs	73.07% <ø> (ø)

... and 2 files with indirect coverage changes

[github-actions[bot]]

Test Results

    3 files  +    1    22 suites  +8   2m 49s :stopwatch: + 1m 29s 144 tests ±    0  144 :heavy_check_mark: ±    0  0 :zzz: ±0  0 :x: ±0  308 runs  +143  308 :heavy_check_mark: +143  0 :zzz: ±0  0 :x: ±0 

Results for commit 9c28747f. ± Comparison against base commit 70c1969a.

This pull request removes 1 and adds 1 tests. Note that renamed tests count towards both.

``` pueue-lib ‑ process_helper::windows::test::test_spawn_command ``` ``` pueue-lib ‑ process_helper::platform::test::test_spawn_command ```