This request appears to be outside the scope of these forums as we do not produce nor provide support for third party products such as phpmyadmin or mariadb. Both of these products have a lot of documentation and community resources for them however so you would try their manufacturer sites.
As far as phpmyadmin this is a separate product that is not used by osTicket in anyway so upgrading it would not impact your osTicket production site, unless their upgrade process requires a complete webserver restart.
MariaDB (the database software) however is used by all applications you have mentioned so far. Upgrading it would impact any site you are running that accesses the database. Upgrading it does involve stopping and starting the database software and would cause a (hopefully) brief outage for all sites you run on that server.
