Nullable: Monitor (#23603)

diff --git a/src/System.Private.CoreLib/src/System/Threading/Monitor.cs b/src/System.Private.CoreLib/src/System/Threading/Monitor.cs
index 2837d90..2701b3b 100644 (file)
--- a/src/System.Private.CoreLib/src/System/Threading/Monitor.cs
+++ b/src/System.Private.CoreLib/src/System/Threading/Monitor.cs
@@ -13,8 +13,7 @@
 **
 =============================================================================*/
 
-
-
+#nullable enable
 using System;
 using System.Runtime;
 using System.Threading;