Assert is not compatible with null safety

[Gama11]

Looks like various Assert methods need to be wrapped in Null<T>:

import utest.Assert;

@:nullSafety
function main() {
	Assert.equals(null, null);
}

source/Main.hx:5: characters 16-20 : Null safety: Cannot pass nullable value to not-nullable argument "expected" of function "equals".
source/Main.hx:5: characters 22-26 : Null safety: Cannot pass nullable value to not-nullable argument "value" of function "equals".

Assert.isNull(null); not working is particularly funny... :D