Reenable Transparent Compiler tests

[majocha]

Experiment branched out from #17872

Async flavor of graph processing is simplified a bit and runs with Async.Parallel, given that it is async already.

If there are any remaining instabilities in Transparent Compiler tests they should be easier to weed out in a parallel test run, where the thread pool is way more stressed.

All the tests tests from #16766 but two should be unskipped, unless I missed some.

[github-actions]

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[majocha]

LruCache Count needs lock. I added a rudimentary fix.

This one I can reproduce locally, but unsure what's going on.