Bump mysql2 from 0.5.3 to 0.5.4
Bump mysql2 from 0.5.3 to 0.5.4

Bumps [mysql2](https://github.com/brianmario/mysql2) from 0.5.3 to 0.5.4.
- [Release notes](https://github.com/brianmario/mysql2/releases)
- [Commits](https://github.com/brianmario/mysql2/compare/0.5.3...0.5.4)

---
updated-dependencies:
- dependency-name: mysql2
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>
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