[loader] Add assembly name matching on netcore to fix DefaultContext test (mono/mono...

[loader] Add assembly name matching on netcore to fix DefaultContext test (mono/mono#18272)

* [loader] Rename assembly name check strictness flag

* [loader] Add predicate for assembly name matching on netcore

* [loader] Enable LoadInDefaultContext test

* Make mono_assembly_names_equal external, change flags in domain search

* Move ifdef inside mono_loader_get_strict_assembly_name_check

* Fix pedump

* No reason to make this external

* Feedback

Commit migrated from https://github.com/mono/mono/commit/33ca3d33e1994cabf9f9b19034624a3495bbc9cb