fixup: rename UserAssertTy to AscribeUserType

This is some rebase pain.

src/librustc_mir/transform/qualify_min_const_fn.rs

@@ -230,7 +230,7 @@ fn check_statement(
         | StatementKind::StorageDead(_)
         | StatementKind::Validate(..)
         | StatementKind::EndRegion(_)
-        | StatementKind::UserAssertTy(..)
+        | StatementKind::AscribeUserType(..)
         | StatementKind::Nop => Ok(()),
     }
 }