Fix foreign key reference in profile SQL query (#4010)

* Fix foreign key reference in profile SQL query

c.id is the primary key on the calls table.  For the first few calls it may be equal to the routine ID, but not for long :-)

* Group by routine ID, too

Author: flwyd

doc/Language/performance.pod6

@@ -100,9 +100,9 @@ opening in SQLite.
           calls c,
           routines r
         where
-          c.id = r.id
+          c.routine_id = r.id
         group by
-          c.id
+          r.id
         order by
           inclusive_time desc
         limit 30;