Update mysql2 to 0.5.2 to support libmariadb and Debian 10

Description

The test Debian 10 machine fails bundle exec rails c with:

See https://gitlab.com/gitlab-org/gitlab-foss/issues/37100.

Environment

None

Status

Assignee

james_

Reporter

james_

Roadmap

Misc

Priority

High

Affects versions

Fix versions

Components

BackEnd

Difficulty

Easy

Required Access Level

None

Epic Link

Milestone

Internal 0.9
Configure