Merge pull request #1152 from jgwerner/fix/update-start-gid

Add -f option with groupadd to gracefully exit when adding existing groups

base-notebook/start.sh

@@ -80,7 +80,7 @@ if [ $(id -u) == 0 ] ; then
     if [ "$NB_UID" != $(id -u $NB_USER) ] || [ "$NB_GID" != $(id -g $NB_USER) ]; then
         echo "Set user $NB_USER UID:GID to: $NB_UID:$NB_GID"
         if [ "$NB_GID" != $(id -g $NB_USER) ]; then
-            groupadd -g $NB_GID -o ${NB_GROUP:-${NB_USER}}
+            groupadd -f -g $NB_GID -o ${NB_GROUP:-${NB_USER}}
         fi
         userdel $NB_USER
         useradd --home /home/$NB_USER -u $NB_UID -g $NB_GID -G 100 -l $NB_USER