There was a crash in JS::CyclicModule::evaluate due to a spec bug that
we worked around years ago (1dc9769f7d).
This bug has now been fixed in ECMA-262. This adds a regression crash
test to ensure we don't crash still after implementing that fix, as this
is really only reachable from an embedder.
Before this change, it was possible for a second GC to get triggered
in the middle of a first GC, due to allocations happening in the
FinalizationRegistry cleanup host hook. To avoid this causing problems,
we add a "post-GC task" mechanism and use that to invoke the host hook
once all other GC activity is finished, and we've unset the "collecting
garbage" flag.
Note that the test included here only fails reliably when running with
the -g flag (collect garbage after each allocation).
Fixes#3051
