This doesn't reduce the quality of tests, because the flags are still
printed for declarations themselves. We only omit them in references.
However, this makes the tests more compatible with non-JVM backends
(see KT-58605), because flags of referenced stdlib declarations may
differ among target platforms.
This only affects JVM IR, and this is similar to how this was done in
the old JVM backend in `CallBasedArgumentGenerator.generateVararg`.
#KT-52146 Fixed