docs: Update Percona random root password generator

Author: mbrodala

percona/content.md

@@ -110,7 +110,7 @@ This is an optional variable. Set to `yes` to allow the container to be started
 
 ### `MYSQL_RANDOM_ROOT_PASSWORD`
 
-This is an optional variable. Set to `yes` to generate a random initial password for the root user (using `pwgen`). The generated root password will be printed to stdout (`GENERATED ROOT PASSWORD: .....`).
+This is an optional variable. Set to `yes` to generate a random initial password for the root user (using `pwmake`). The generated root password will be printed to stdout (`GENERATED ROOT PASSWORD: .....`).
 
 ### `MYSQL_ONETIME_PASSWORD`