Update HzMemoryCache/Diagnostics/TrashingDetector.cs

Co-authored-by: Copilot <[email protected]>

Author: JoelNygren-Norce

HzMemoryCache/Diagnostics/TrashingDetector.cs

@@ -2,7 +2,7 @@ namespace HzCache.Diagnostics
 {
     internal class TrashingDetector
     {
-        public string Checksum { get; set; }
-        public int Counter { get; set; }
+        public string? Checksum { get; set; } = null;
+        public int Counter { get; set; } = 0;
     }
 }