Fix typos in git_tips.md doc.

[email protected]

Review-Url: https://codereview.chromium.org/2786413004
Cr-Commit-Position: refs/heads/master@{#461206}
diff --git a/AUTHORS b/AUTHORS
index ddf6f67..c8fe034e 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -8,6 +8,7 @@
 #
 # See python fnmatch module documentation for more information.
 
+Aaron Boushley <[email protected]>
 Aaron Jacobs <[email protected]>
 Aaron Leventhal <[email protected]>
 Aaron Randolph <[email protected]>