fix (project-clone) : update user_setup script to modify /etc/passwd permissions/ownership (#1499)

Update user_setup script to not make `/etc/passwd` group writable

Signed-off-by: Rohan Kumar <[email protected]>

Author: rohanKanojia

build/bin/user_setup

@@ -6,8 +6,7 @@ mkdir -p ${HOME}
 chown ${USER_UID}:0 ${HOME}
 chmod ug+rwx ${HOME}
 
-# runtime user will need to be able to self-insert in /etc/passwd
-chmod g+rw /etc/passwd
+chmod g-w /etc/passwd
 
 # no need for this script to remain in the image after running
 rm $0