Correct `--integrity-exclude` package name matching logic

[ericcornelissen]

Description

Update the matching logic for --integrity-exclude to check the excluded package name against the package identifier used internally. Update the corresponding test suite with more realistic mocking data. Add an extra test case to ensure package names aren't matched partially.

Types of changes

• [x] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Related Issue

Followup to #188

Motivation and Context

n/a

How Has This Been Tested?

• Unit testing (as seen in the diff)
• End-to-end testing (linked my clone of this project to the project mentioned in #187 and checked that the configuration behaved as expected)

Screenshots (if appropriate):

Checklist:

• [ ] I have updated the documentation (if required).
• [x] I have read the CONTRIBUTING document.
• [x] I have added tests to cover my changes.
• [x] All new and existing tests passed.
• [ ] I added a picture of a cute animal cause it's fun

docs don't apply; no new cute animal picture, sorry

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Comparison is base (9c03af3) 98.01% compared to head (8546344) 98.01%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #190 +/- ## ======================================= Coverage 98.01% 98.01% ======================================= Files 13 13 Lines 403 403 Branches 96 96 ======================================= Hits 395 395 Misses 8 8 ```

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