Merge pull request 'Added solved_count to listproblems endpoint' (#2) from listproblems-solved-count into develop

Reviewed-on: #2
Reviewed-by: Vyacheslav Birin <vyacheslav1557@noreply.localhost>
Reviewed-by: Holoti <holoti@noreply.localhost>

internal/tester/delivery/rest/handlers.go

@@ -467,6 +467,7 @@ func PLI2PLI(p models.ProblemsListItem) testerv1.ProblemsListItem {
 		TimeLimit:   p.TimeLimit,
 		CreatedAt:   p.CreatedAt,
 		UpdatedAt:   p.UpdatedAt,
+		SolvedCount: p.SolvedCount,
 	}
 }