Fix eventloop usage for haxe 5

[tobil4sk]

Haxe 5 nightlies have a new api for event loops: HaxeFoundation/haxe#12388

See the equivalent heaps patch: HeapsIO/heaps@d40f2d0#diff-c0fa4e889efa97012174175edcce85cc359792651eb5e7435d2f0c0ed26dec0a

[tobil4sk]

I think this needs to be updated too:

lime/src/lime/system/JNI.hx

Line 470 in 17fe047

haxe.MainLoop.runInMainThread($i{field.name}.bind($a{args}))

Also, this will have the same issue as the openfl dictionary size PR since haxe 5 preview 1 didn't have this updated api yet.