Remove redundant suppression

Author: bkoelman

test/TestBuildingBlocks/NullabilityAssertionExtensions.cs

@@ -2,7 +2,6 @@
 using JetBrains.Annotations;
 using SysNotNull = System.Diagnostics.CodeAnalysis.NotNullAttribute;
 
-// ReSharper disable PossibleMultipleEnumeration
 #pragma warning disable CS8777 // Parameter must have a non-null value when exiting.
 
 namespace TestBuildingBlocks;