MDEV-5303 rpm post-inst scriptlet creates mysql user with a valid shell

create mysql user with /sbin/nologin shell

support-files/rpm/server-postin.sh

@@ -23,9 +23,9 @@ if [ $1 = 1 ] ; then
   # Create a MySQL user and group. Do not report any problems if it already
   # exists.
   groupadd -r %{mysqld_group} 2> /dev/null || true
-  useradd -M -r -d $datadir -s /bin/bash -c "MySQL server" -g %{mysqld_group} %{mysqld_user} 2> /dev/null || true 
+  useradd -M -r --home $datadir --shell /sbin/nologin --comment "MySQL server" --gid %{mysqld_group} %{mysqld_user} 2> /dev/null || true 
   # The user may already exist, make sure it has the proper group nevertheless (BUG#12823)
-  usermod -g %{mysqld_group} %{mysqld_user} 2> /dev/null || true
+  usermod --gid %{mysqld_group} %{mysqld_user} 2> /dev/null || true
 
   # Change permissions so that the user that will run the MySQL daemon
   # owns all database files.