[Test] Coverage of admission package

[dacappo]

Description

Unit-tests for the admission (karydia) package to increase code coverage.

Checklist

Before submitting this PR, please make sure:

• [x] you have added unit tests
• [x] your code builds clean with make
• [x] your code lets succeed unit tests with make test

[ionysos]

@dacappo could you please resolve the merge conflicts first?