Sema: Don't remove nonisolated attribute when we diagnose it as invalid on 'lazy'

Fixes rdar://141967932.

Author: slavapestov

lib/Sema/TypeCheckAttr.cpp

@@ -7449,7 +7449,7 @@ void AttributeChecker::visitNonisolatedAttr(NonisolatedAttr *attr) {
     }
 
     if (var->getAttrs().hasAttribute<LazyAttr>()) {
-      diagnoseAndRemoveAttr(attr, diag::nonisolated_lazy)
+      diagnose(attr->getLocation(), diag::nonisolated_lazy)
         .warnUntilSwiftVersion(6);
       return;
     }