fixes #24378; supportsCopyMem can fail from macro context with tuples (#24383)

fixes #24378

```nim
type Win = typeof(`body`)
doAssert not supportsCopyMem((int, Win))
```

`semAfterMacroCall` doesn't skip the children aliases types in the tuple
typedesc construction while the normal program seem to skip the aliases
types somewhere

`(int, Win)` is kept as `(int, alias string)` instead of expected `(int,
string)`

compiler/ast.nim

@@ -1645,7 +1645,7 @@ proc propagateToOwner*(owner, elem: PType; propagateHasAsgn = true) =
   if mask != {} and propagateHasAsgn:
     let o2 = owner.skipTypes({tyGenericInst, tyAlias, tySink})
     if o2.kind in {tyTuple, tyObject, tyArray,
-                   tySequence, tySet, tyDistinct}:
+                   tySequence, tyString, tySet, tyDistinct}:
       o2.flags.incl mask
       owner.flags.incl mask