I disagree; when at all possible, you want to make the clustered index unique yourself whenever possible. Yes, SQL will always force it to be unique anyway, but that often leads to performance loss in all sorts of queries where you wouldn't suspect it.
Also, since row compression is available for your version of SQL (2016), you should definitely strongly consider that as well. ROW compression is usually a given, PAGE is often valuable but you should verify it first. The only time you wouldn't do that is if you are severely CPU constrained.
You should also explicitly specify FILLFACTOR. Again, the proper value varies, but that's actually a good reason to explicitly specify it: it makes you consider the best FF for that specific index.
Putting this all into action for your situation, you might try:
CREATE UNIQUE CLUSTERED INDEX [Table__CL_Parent_Id] ON [dbo].[Table]
[Parent_Id] , Table_Id
) WITH ( DATA_COMPRESSION = PAGE /*ROW*/, FILLFACTOR = 98, SORT_IN_TEMPDB = ON ) ON [PRIMARY]
SQL DBA,SQL Server MVP(07, 08, 09) Prosecutor James Blackburn, in closing argument in the Fatal Vision murders trial: If in the future, you should cry a tear, cry one for them [the murder victims]. If in the future, you should say a prayer, say one for them. And if in the future, you should light a candle, light one for them.