completion: complete AUTO_MERGE

The pseudoref AUTO_MERGE is documented since the previous commit. To
make it easier to use, let __git_refs in the Bash completion code
complete it.

Signed-off-by: Philippe Blain <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: phil-blain

contrib/completion/git-completion.bash

@@ -767,7 +767,7 @@ __git_refs ()
 			track=""
 			;;
 		*)
-			for i in HEAD FETCH_HEAD ORIG_HEAD MERGE_HEAD REBASE_HEAD CHERRY_PICK_HEAD REVERT_HEAD BISECT_HEAD; do
+			for i in HEAD FETCH_HEAD ORIG_HEAD MERGE_HEAD REBASE_HEAD CHERRY_PICK_HEAD REVERT_HEAD BISECT_HEAD AUTO_MERGE; do
 				case "$i" in
 				$match*|$umatch*)
 					if [ -e "$dir/$i" ]; then