Don't load OAuth Twitter library in Dæghrefn

Summary:
As Twitter support is removed from our IRC bots,
we don't need this library anymore.

Ref T1795

Test Plan: Ensure eggdrops start safely

Reviewers: dereckson

Reviewed By: dereckson

Maniphest Tasks: T1795

Differential Revision: https://devcentral.nasqueron.org/D2884