Include class template invocation index in legacy reporting names (Backport to 5.14)

[amilbourne]

This is a backport of commit b9756dd which stems from #5409 & #5441

Changes were made to compile under Java 8

I have updated release notes but not sure if this is the correct procedure.
If this PR is OK, I can also backport #5524

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Definition of Done

• [ x ] There are no TODOs left in the code
• [ x ] Method preconditions are checked and documented in the method's Javadoc
• [ x ] Coding conventions (e.g. for logging) have been followed
• [ x ] Change is covered by automated tests including corner cases, errors, and exception handling
• [ x ] Public API has Javadoc and @API annotations
• [ x ] Change is documented in the User Guide and Release Notes

[amilbourne]

@marcphilipp Is this backport OK?

[marcphilipp]

@amilbourne Yes, we need to discuss what else to backport and when first, though. I'll eventually get back to you but it may take some time.