[ContextManager] Remove the put/get free context cycle
The put/get free context cycle in ContextManager::start() (if continuation stealing is enabled) became unnecessary with c66551bf ("[Context] Use 'jmp' instead of 'ret' to kickoff the context").
The put/get free context cycle in ContextManager::start() (if continuation stealing is enabled) became unnecessary with c66551bf ("[Context] Use 'jmp' instead of 'ret' to kickoff the context").