Add test for #7250

Author: odersky

tests/pos/i7250.scala

@@ -0,0 +1,11 @@
+import compiletime.erasedValue
+
+sealed trait Foo
+trait A extends Foo
+trait B[H] extends Foo
+
+inline given f[T <: Foo]: T = inline erasedValue[T] match
+  case _: A => new A{}.asInstanceOf[T]
+  case _: B[a] => summon[a].asInstanceOf[T]
+
+@main def Test = println(f[B[Int]])