[oslo] Proposing Zane Bitter as general Oslo core

Hi all, Zane is already core on oslo.service, but he's been doing good stuff in adjacent projects as well. We could keep playing whack-a-mole with giving him +2 on more repos, but I trust his judgment so I'm proposing we just add him to the oslo-core group. If there are no objections in the next week I'll proceed with the addition. Thanks. -Ben