Fix workdir flag for celery with 5.0 change

Move workdir to global flag per https://docs.celeryproject.org/en/stable/whatsnew-5.0.html?highlight=workdir#new-command-line-interface

Signed-off-by: Corey Shields <cshields@gmail.com>

bin/djangoctl.sh

@@ -72,7 +72,7 @@ run() {
 run_celery() {
 	case "$1" in
 		worker|beat)
-			exec celery -A "$DJANGO_APP" "$1" -l INFO --workdir "$CELERY_VAR_RUN"
+			exec celery --workdir "$CELERY_VAR_RUN" -A "$DJANGO_APP" "$1" -l INFO
 			;;
 		*)
 			usage