Fix exit code check and virtual manifest parsing (RustCli)

[codecov[bot]]

Codecov Report

Attention: 4 lines in your changes are missing coverage. Please review.

Comparison is base (ae7438f) 74.9% compared to head (9edebfe) 74.9%.

Files	Patch %	Lines
...mponentDetection.Detectors/rust/RustCliDetector.cs	42.8%	3 Missing and 1 partial :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #937 +/- ## ======================================= - Coverage 74.9% 74.9% -0.1% ======================================= Files 235 235 Lines 9991 9996 +5 Branches 980 981 +1 ======================================= + Hits 7487 7488 +1 - Misses 2231 2234 +3 - Partials 273 274 +1 ```

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[github-actions[bot]]

👋 Hi! It looks like you modified some files in the Detectors folder. You may need to bump the detector versions if any of the following scenarios apply:

• The detector detects more or fewer components than before
• The detector generates different parent/child graph relationships than before
• The detector generates different devDependencies values than before

If none of the above scenarios apply, feel free to ignore this comment 🙂