remove dead code

[Brambor]

Summary

None

Purpose of change

Remove dead code.

Describe the solution

Describe alternatives you've considered

Use it to replace instances of m_runtimes[ id ].reset( def );, which I didn't realize at first is adding to m_runtimes by reset to def.

Testing

Should compile.

Additional context

• Found in Compute can_holser once per save to speed up d: filter from ~20s to ~5s #78950.