Fix minor doc inconsistencies around mariadb invokation

[topiaruss]

Description

The second SQL mariadb command had the old image version. Both invokations used 'mysql' which is deprecated.

Fixes # NONE

How Has This Been Tested?

Both commands were checked in editor preview for formatting, and successfully executed from a terminal.

[adamjensenbot]

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[aleoli]

/rebase test=true

[aleoli]

Hi @topiaruss! Thanks for your work! Can you squash your commits, please?