Update behavior of zero-length lists/strings (#4648)

The spec was expected to change to not bounds-check 0-byte lists/strings
but has since been updated to match `memory.copy` which does indeed
check the pointer for 0-byte copies.

tests/misc_testsuite/component-model/adapter.wast

@@ -130,4 +130,4 @@
   )
   (export "empty-list" (func $f))
 )
-(assert_return (invoke "empty-list" (list.const)) (unit.const))
+(assert_trap (invoke "empty-list" (list.const)) "realloc return: beyond end of memory")