Override ARGS and fail correctly

See https://github.com/Coop-Cloud/peertube/issues/1.

abra

@@ -1841,10 +1841,12 @@ sub_app_run(){
     RUN_USER="-u $abra___user"
   fi
 
+  local -a ARGS="${ARGS:-""}"
+
   if [ "$abra___no_tty" = "true" ]; then
-    ARGS="-i"
+    ARGS+=" -i"
   else
-    ARGS="-it"
+    ARGS+=" -it"
   fi
 
   CONTAINER=$(docker container ls --format "table {{.ID}},{{.Names}}" \
@@ -1856,11 +1858,12 @@ sub_app_run(){
   fi
 
   debug "Using container ID ${CONTAINER}"
+  debug "Running command: docker exec $RUN_USER "$ARGS" "$CONTAINER" "$@""
 
-  # 3wc: we want the "splitting" that shellcheck warns us about, so that -u and
-  # $RUN_USER aren't treated as a single argument:
   # shellcheck disable=SC2086
-  docker exec $RUN_USER $ARGS "$CONTAINER" "$@"
+  if ! docker exec $RUN_USER "$ARGS" "$CONTAINER" "$@"; then
+    exit 1
+  fi
 
   return
 }