C#: Add `precision` tag to `cs/deserialized-delegate`

csharp/ql/src/Security Features/CWE-502/DeserializedDelegate.ql

@@ -5,14 +5,11 @@
  * @kind problem
  * @id cs/deserialized-delegate
  * @problem.severity warning
+ * @precision high
  * @tags security
  *       external/cwe/cwe-502
  */
 
-/*
- * consider: @precision high
- */
-
 import csharp
 import semmle.code.csharp.frameworks.system.linq.Expressions
 import semmle.code.csharp.serialization.Deserializers