No or incorrect coverage on expression body members

[anddrzejb]

Describe the bug
Seems to me there is a problem with covering expression body members. When I try to run coverage for them, there are often false partially covered lines, instead of all lines covered.

To Reproduce
In the repro code there is a static class Mapper that contains 2 methods that are tested:

• Mapper.MapConcise - uses expression body members
• Mapper.MapVerbose - uses step-by-step approach

Both methods have exactly the same set of tests.

Expected behavior
Both methods should generate 100% code coverage.

Actual behavior
Only Mapper.MapVerbose produces 100%. The Mapper.MapConcise produces a lot of partially not covered lines:

Configuration (please complete the following information):
Please provide more information on your .NET configuration:
* Which coverlet package and version was used? 6.0.2.
* Which version of .NET is the code running on? .net8
* What OS and version, and what distro if applicable? Windows 11 10.0.22631 Build 22631
* What is the architecture (x64, x86, ARM, ARM64)? x64
* Do you know whether it is specific to that configuration? It is not specific to my configuration.

Additional context
I have a very similar code run on azure devops with the same problem. The verbose code goes through without any problem, the concise is breaking my builds (I have 70% code coverage set with evaluation on changes only and it often blocks my CI).