[yuyi98]

This PR check error for sumtype in array (fix #19170).

• Check error for sumtype in array.
• Add test.

struct OtherType {
	foo string
	bar string
}

type RuneAlias = rune
type RuneAliasOrOtherType = OtherType | RuneAlias

const whitespace = [rune(0x0009), 0x000a, 0x000c, 0x000d, 0x0020]

fn main() {
	mut x := RuneAliasOrOtherType(RuneAlias(rune(`!`)))
	match x {
		RuneAlias {
			if x in whitespace {
				// doing `if x as RuneAlias in whitepsace` here
				// works but it should be doing that automatically
				// since I'm inside the RuneAlias match condition.
			}
		}
		else {
			// do something else
		}
	}
}

PS D:\Test\v\tt1> v run .       
tt1.v:15:7: error: left operand to `in` does not match the array element type: expected `rune`, not `RuneAliasOrOtherType`
   13 |     match x {
   14 |         RuneAlias {
   15 |             if x in whitespace {
      |                ~~~~~~~~~~~~~~~
   16 |                 // doing `if x as RuneAlias in whitepsace` here
   17 |                 // works but it should be doing that automatically