Add a test on nested quoted patterns

Author: nicolasstucki

tests/pos/i6214b.scala

@@ -0,0 +1,8 @@
+object Test {
+  def res(x: quoted.Expr[Int]) given tasty.Reflection: quoted.Expr[Int] = x match {
+    case '{ val a: Int = ${ Foo('{ val b: Int = $y; b }) }; a } => y // owner of y is res
+  }
+  object Foo {
+    def unapply(x: quoted.Expr[Int]): Option[quoted.Expr[Int]] = Some(x)
+  }
+}