Merged PR 35490: Fixing VerifyCertificate NET 6.0

Adding a check to return NotValidForUsage status when there is an internal failure occurred in chain.Build

Author: Kuldeep-MS

src/Microsoft.DotNet.Wpf/src/WindowsBase/System/IO/Packaging/PackageDigitalSignatureManager.cs

@@ -836,6 +836,14 @@ public static X509ChainStatusFlags VerifyCertificate(X509Certificate certificate
             if (!valid)
             {
                 X509ChainStatus[] chainStatus = chain.ChainStatus;
+
+                //check if build has experienced any internal failure
+                if (chainStatus.Length == 0)
+                {
+                    //Internal failure has occurred while building
+                    return X509ChainStatusFlags.NotValidForUsage;
+                }
+                
                 for (int i = 0; i < chainStatus.Length; i++)
                 {
                     status |= chainStatus[i].Status;