Only escape spaces in paths for find

Summary: We use `*` wildcards in an include and that doesn't go well if we are
passing the paths as strings to find.

Reviewed By: @avikchaudhuri

Differential Revision: D1697791

Signature: t1:1697791:1416600893:f76659575bc23cb6dee8f20ac2f6b1fdcb5a8cb9