travis-ci: handle Git for Windows CI status "failed" explicitly

Git for Windows CI returns "completed: failed" if a build or test
failure happened. This case was processed as "Unhandled status".
Handle the case explicitly.

Signed-off-by: Lars Schneider <larsxschneider@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

ci/run-windows-build.sh

@@ -61,7 +61,8 @@ do
 	case "$STATUS" in
 	inProgress|postponed|notStarted) sleep 10               ;; # continue
 		 "completed: succeeded") RESULT="success"; break;; # success
-	*) echo "Unhandled status: $STATUS";               break;; # failure
+		    "completed: failed")                   break;; # failure
+	*) echo "Unhandled status: $STATUS";               break;; # unknown
 	esac
 done