MB-52195 Tag "system" collections in bucket manifest

This change adds {"system": true} to the system collections. Currently
these are _query, _mobile, _eventing.

Change-Id: I82d44faea92f72853f124f4ddbcf53d3145ca1d7
Reviewed-on: https://review.couchbase.org/c/ns_server/+/175452
Well-Formed: Build Bot <build@couchbase.com>
Tested-by: Steve Watanabe <steve.watanabe@couchbase.com>
Tested-by: Build Bot <build@couchbase.com>
Reviewed-by: Bryan McCoid <bryan.mccoid@couchbase.com>

src/collections.erl

@@ -129,7 +129,7 @@ manifest_with_system_scope() ->
     {NextId, Collections} =
         lists:foldl(
           fun (Name, {Id, Cols}) ->
-                  {Id + 1, [{Name, [{uid, Id}]}] ++ Cols}
+                  {Id + 1, [{Name, [{uid, Id}, {"system", true}]}] ++ Cols}
           end, {8, []}, system_collections()),
 
     [{uid, 0},