Address review

Author: liufengyun

compiler/src/dotty/tools/dotc/core/TypeComparer.scala

@@ -1083,7 +1083,6 @@ class TypeComparer(initctx: Context) extends ConstraintHandling[AbsentContext] {
           case tparam: Symbol
           if leftRoot.isStable || (ctx.isAfterTyper || ctx.mode.is(Mode.TypevarsMissContext)) && leftRoot.member(tparam.name).exists =>
             val captured = TypeRef(leftRoot, tparam)
-            assert(captured.exists, i"$leftRoot has no member $tparam in isSubArgs($args1, $args2, $tp1, $tparams2)")
             isSubArg(captured, arg2)
           case _ =>
             false