[runtime] Convert more icalls to use handles. (#15862)
* [runtime] Convert Volatile to use the same approach as the netcore version, get rid of most Volatile icalls.
* [runtime] Reduce the number of handles used by construct_culture ().
* [runtime] Convert some icalls to handles.
* Fix signature of FAMNextEvent.
* [aot] Avoid aoting the gsharedvt versions of Volatile:Read<T>/Write<T>.
* Bump API snapshot submodule
* Convert Marshal:UnsafeAddrOfPinnedArrayElement to use coop handles.
14 files changed: