Bump mysql2 from 2.3.3 to 3.9.4

Bumps [mysql2](https://github.com/sidorares/node-mysql2) from 2.3.3 to 3.9.4.
- [Release notes](https://github.com/sidorares/node-mysql2/releases)
- [Changelog](https://github.com/sidorares/node-mysql2/blob/master/Changelog.md)
- [Commits](sidorares/node-mysql2@v2.3.3...v3.9.4)

---
updated-dependencies:
- dependency-name: mysql2
  dependency-type: indirect
...

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

yarn.lock

@@ -3577,7 +3577,7 @@ mute-stream@~0.0.4:
 
 mysql2@^2.1.0:
   version "2.3.3"
-  resolved "https://registry.npmjs.org/mysql2/-/mysql2-2.3.3.tgz"
+  resolved "https://registry.yarnpkg.com/mysql2/-/mysql2-2.3.3.tgz#944f3deca4b16629052ff8614fbf89d5552545a0"
   integrity sha512-wxJUev6LgMSgACDkb/InIFxDprRa6T95+VEoR+xPvtngtccNH2dGjEB/fVZ8yg1gWv1510c9CvXuJHi5zUm0ZA==
   dependencies:
     denque "^2.0.1"