Merged PR 15469: Clean up logging (#35241)

Clean up logging

Co-authored-by: Hao Kung <haok@microsoft.com>

src/Security/Authentication/JwtBearer/src/JwtBearerHandler.cs

@@ -181,7 +181,7 @@ namespace Microsoft.AspNetCore.Authentication.JwtBearer
                     return AuthenticateResult.Fail(authenticationFailedContext.Exception);
                 }
 
-                return AuthenticateResult.Fail("No SecurityTokenValidator available for token: " + token ?? "[null]");
+                return AuthenticateResult.Fail("No SecurityTokenValidator available for token.");
             }
             catch (Exception ex)
             {