The big ones here are `trim-trailing-whitespace` and `end-of-file-fixer`
(which makes sure that every file ends with exactly one newline
character).
Change-Id: Idca73b640883188f068f9903e013cf0d82aa1123
initialize test suite for git fetchers
(cherry picked from commit 0bd9e10aea747df51c8a5af124864c722cbeafde)
Change-Id: Idf94a47794190c3e1de07fc4e7848741c4e9ffed