[C#] Using C API fails at runtime when targeting .NET 4.7.2

[CurtHagenlocher]

Describe the bug, including details regarding any error messages, version, and platform.

The code fails with an error message along the lines of "Cannot marshal 'parameter #1': Pointers cannot reference marshaled structures. Use ByRef instead."

Component(s)

C#

[kou]

Can we verify this case in our verification script?

[CurtHagenlocher]

I have a separate PR (#36818) which enables testing under .NET 4.7.2 under Windows. (Unfortunately, I didn't figure out how to do this in time to add it to the previous PR.) Arguably, a better approach would be to build for 4.7.2 on every platform but enable the test only under Windows. Unfortunately, I didn't have the time to figure out how to modify the CI scripts to manage that; they currently seem to run all the tests that are built which means that they would try to run the 4.7.2 tests even on platforms where it's not supported.