⬆️ Bump mysql2 in /services/blockchain-app-registry

Bumps [mysql2](https://github.com/sidorares/node-mysql2) from 3.9.4 to 3.9.7.
- [Release notes](https://github.com/sidorares/node-mysql2/releases)
- [Changelog](https://github.com/sidorares/node-mysql2/blob/master/Changelog.md)
- [Commits](sidorares/node-mysql2@v3.9.4...v3.9.7)

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

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

services/blockchain-app-registry/yarn.lock

@@ -3290,9 +3290,9 @@ ms@2.1.3, ms@^2.1.1:
   integrity sha512-6FlzubTLZG3J2a/NVCAleEhjzq5oxgHyaCU9yYXvcLsvoVaHJq/s5xXI6/XXP6tz7R9xAOtHnSO/tXtF3WRTlA==
 
 mysql2@^3.5.2:
-  version "3.9.4"
-  resolved "https://registry.yarnpkg.com/mysql2/-/mysql2-3.9.4.tgz#0d4f666015f8ed213aa6f2f5e59065eb99d7c3de"
-  integrity sha512-OEESQuwxMza803knC1YSt7NMuc1BrK9j7gZhCSs2WAyxr1vfiI7QLaLOKTh5c9SWGz98qVyQUbK8/WckevNQhg==
+  version "3.9.7"
+  resolved "https://registry.yarnpkg.com/mysql2/-/mysql2-3.9.7.tgz#843755daf65b5ef08afe545fe14b8fb62824741a"
+  integrity sha512-KnJT8vYRcNAZv73uf9zpXqNbvBG7DJrs+1nACsjZP1HMJ1TgXEy8wnNilXAn/5i57JizXKtrUtwDB7HxT9DDpw==
   dependencies:
     denque "^2.1.0"
     generate-function "^2.3.1"