Bump mysql2 from 2.1.0 to 3.9.8

Bumps [mysql2](https://github.com/sidorares/node-mysql2) from 2.1.0 to 3.9.8.
- [Release notes](https://github.com/sidorares/node-mysql2/releases)
- [Changelog](https://github.com/sidorares/node-mysql2/blob/master/Changelog.md)
- [Commits](sidorares/node-mysql2@v2.1.0...v3.9.8)

---
updated-dependencies:
- dependency-name: mysql2
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

package-lock.json

@@ -40,7 +40,7 @@
     "@types/node": "^13.5.3",
     "dotenv": "^8.2.0",
     "jest": "^25.1.0",
-    "mysql2": "^2.1.0",
+    "mysql2": "^3.9.8",
     "ts-jest": "^25.1.0",
     "typescript": "^3.7.5"
   }