Use variable for Interceptor check

Author: bahusoid

src/NHibernate/Async/Engine/ForeignKeys.cs

@@ -187,8 +187,9 @@ public static async Task<bool> IsNotTransientSlowAsync(string entityName, object
 				}
 
 				// let the interceptor inspect the instance to decide
-				if (session.Interceptor.IsTransient(entity) is bool transient)
-					return Task.FromResult<bool?>(transient);
+				var isTransient = session.Interceptor.IsTransient(entity);
+				if (isTransient.HasValue)
+					return Task.FromResult<bool?>(isTransient);
 
 				if (entity is INHibernateProxy proxy && proxy.HibernateLazyInitializer.IsUninitialized)
 				{

src/NHibernate/Engine/ForeignKeys.cs

@@ -179,8 +179,9 @@ public static bool IsNotTransientSlow(string entityName, object entity, ISession
 			}
 
 			// let the interceptor inspect the instance to decide
-			if (session.Interceptor.IsTransient(entity) is bool transient)
-				return transient;
+			var isTransient = session.Interceptor.IsTransient(entity);
+			if (isTransient.HasValue)
+				return isTransient;
 
 			if (entity is INHibernateProxy proxy && proxy.HibernateLazyInitializer.IsUninitialized)
 			{