Fix pytest bzl rule to not override deps
Fix pytest bzl rule to not override deps

Summary: .

Reviewed By: irenewchen

shipit-source-id: 8004229beecf18f940886475a067af67c5425769

JoelMarcey/buck,JoelMarcey/buck,JoelMarcey/buck,JoelMarcey/buck,JoelMarcey/buck,JoelMarcey/buck,JoelMarcey/buck,JoelMarcey/buck,JoelMarcey/buck,JoelMarcey/buck,JoelMarcey/buck,JoelMarcey/buck,JoelMarcey/buck