Multi-release project doesn't wire references into an MR-jar correctly

[stephan-herrmann]

When an MR-project references an MR-jar in its dependencies, I expect that files in the project's src17 folder can see classfiles within the MR-jar file's META-INF/versions/17 tree.

This is the case for the builder but not for the reconciler.

[stephan-herrmann]

Client.zip

Import the above project into your workspace. The Problems view will be clean, but in the editor you'll see /Client/src17/client/Test.java decorated with with an error: lib.Helper17 cannot be resolved to a type.

[laeubi]

I'll try to take a look once #4534 was done to not open too much places at once. It might even be the case that this fixes some things in that area because it includes also more places to use a release at all.