A threshold of 2% is set in codecov.yml.
https://github.com/microsoft/msquic/blob/main/codecov.yml.

The threshold is needed because some tests used by coverage data have randomized behavior and might not hit exactly the same lines of code on each runs.

However, the CI is failing with smaller percentage, like in #5315.
(project code coverage moved by less than 2%).

The configuration should enforce that:

• every patch has at least 80% coverage, ignoring documentation (all *.md files)
• every PR does not reduce the project coverage by more than 2%