Fix the UTs

Author: thabart

src/IdServer/SimpleIdServer.IdServer/Api/Authorization/Validators/OAuthAuthorizationRequestValidator.cs

@@ -228,10 +228,13 @@ public virtual async Task ValidateAuthorizationRequestWhenUserIsAuthenticated(Gr
                     throw new OAuthException(ErrorCodes.INVALID_REQUEST, string.Format(Global.InvalidClaims, string.Join(",", invalidClaims.Select(i => i.Name))));
             }
 
-            var acr = await _amrHelper.FetchDefaultAcr(context.Realm, acrValues, claims, openidClient, cancellationToken);
-            var notAuthorizedAmrs = acr.AuthenticationMethodReferences.Where(c => !context.Request.Amrs.Contains(c));
-            if (notAuthorizedAmrs.Any())
-                throw new OAuthAuthenticatedUserAmrMissingException(acr.Name, notAuthorizedAmrs.First(), acr.AuthenticationMethodReferences);
+            if(context.Request.Amrs.Any())
+            {
+                var acr = await _amrHelper.FetchDefaultAcr(context.Realm, acrValues, claims, openidClient, cancellationToken);
+                var notAuthorizedAmrs = acr.AuthenticationMethodReferences.Where(c => !context.Request.Amrs.Contains(c));
+                if (notAuthorizedAmrs.Any())
+                    throw new OAuthAuthenticatedUserAmrMissingException(acr.Name, notAuthorizedAmrs.First(), acr.AuthenticationMethodReferences);
+            }
         }
 
         protected virtual void RedirectToConsentView(HandlerContext context)