Execute test plan with the deployment classloader as the TCCL

[aloubyansky]

Fix #24229

[aloubyansky]

I should add a test though

[famod]

Yeah, test would be nice.

Apart from that: LGTM; I tested it successfully in my real project and Stuart already said it's the proper way.
I'm only asking myself what's left for which we need the augmentation classloader (set in ModuleTestRunner)?

[famod]

PS: IMO it makes sense to backport, but I'll leave this to you.

[gsmet]

@aloubyansky do you plan on adding the test soon or should we merge?

[aloubyansky]

Yes, I'll look into adapting the reproducer provided by @famod

[gsmet]

@aloubyansky I will merge this tonight latest as I want this in CR1. If you don't have the time to write the test now, no biggie, we can include it later.

[aloubyansky]

Unfortunately, I couldn't create a test case that would fail. I tried using ContinuousTestingTestUtils as a base utility but my test would still pass for 2.7.5.Final. Looks like we need a "cleaner" test framework for CT. Let's merge this one for now.