Breaking change fix for ConcurrencyStamp to initialize with new Guid. (#57553)

Co-authored-by: Adit Sheth <[email protected]>

Author: shethaadit

src/Identity/Extensions.Stores/src/IdentityRole.cs

@@ -72,7 +72,7 @@ public IdentityRole(string roleName) : this()
     /// <summary>
     /// A random value that should change whenever a role is persisted to the store
     /// </summary>
-    public virtual string? ConcurrencyStamp { get; set; }
+    public virtual string? ConcurrencyStamp { get; set; } = Guid.NewGuid().ToString();
 
     /// <summary>
     /// Returns the name of the role.