Update tests to meet 80%+ coverage target

[GuusLieben]

Related problem

Since #898 we enforce code coverage for all modules, however we have not yet met this target for the entire project.

Requested feature

Before 23.1 can be released, we need to ensure the code coverage target of 80% or more coverage is met. Investigate which projects are lacking sufficient tests at this time. Based on this investigation we can prepare and execute a test plan to ensure the coverage target is met, and tests remain logical.