Changes all fbandroid python2 shebangs to python3.
Changes all fbandroid python2 shebangs to python3.

Reviewed By: jiawei-lyu

Differential Revision: D35326378

fbshipit-source-id: 733edc4deb0a8bb26e0ae0b679a1cf6260c3c3d8

facebook/fresco,facebook/fresco,facebook/fresco,facebook/fresco,facebook/fresco,facebook/fresco