rbash: put restrictions onto 1 line

pages/common/rbash.md

@@ -1,14 +1,7 @@
 # rbash
 
 > Restricted Bash shell.
-> Restrictions implemented in rbash.
-> The cd command is not allowed.
-> PATH and ENV (setting/unsetting).
-> Importing function.
-> Specifying file name containing argument ‘/’.
-> Specifying file name containing argument ‘-‘.
-> Redirecting output using ‘>‘, ‘>>‘, ‘>|‘, ‘<>‘, ‘>&‘, ‘&>‘.
-> Turning off restriction using ‘set +r‘ or ‘set +o‘.
+> Restrictions implemented in rbash: the cd command is not allowed,PATH and ENV (setting/unsetting),importing function,specifying file name containing argument ‘/’,specifying file name containing argument ‘-‘,redirecting output using ‘>‘, ‘>>‘, ‘>|‘, ‘<>‘, ‘>&‘, ‘&>‘,turning off restriction using ‘set +r‘ or ‘set +o‘.
 
 - Start rbash: