fix(osqp_interface): memory leak problem

[rej55]

Related Issue(required)

Description(required)

There are memory leak problems in the nodes using osqp_interface.
To fix this problem, I changed the type of m_work from a raw pointer to std::unique_ptr.

Review Procedure(required)

Check memory usage of control_container, for example.

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[TakaHoribe]

Confirmed the memory leak problem has been solved.