[C] Unit test setup & connection settings tests

[vaavva]

Purpose

• Adds unit test framework & instructions for C
• Adds running unit tests to the pipeline
• Adds unit tests for setting connection settings in C

Checklist

• [x] I have read the contribution guidelines.
• I submitted this PR against the correct branch:
  • [x] This pull-request is submitted against the main branch.
  • [x] I have merged the latest main branch prior to submission and re-merged as needed after I took any feedback.
  • [x] I will squashed my changes into one with a clear description of the change when I complete the PR.

Does this introduce a breaking change?

[ ] Yes
[x] No

Pull Request Type

What kind of change does this Pull Request introduce?

[ ] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Documentation content changes
[x] Other... Please describe: Tests

How to Test

• ...

What to Check

Verify that the following are valid

• ...

Other Information