⬆️ maint(deps-dev): Bump @types/supertest in /packages/server

Bumps [@types/supertest](https://github.com/DefinitelyTyped/DefinitelyTyped/tree/HEAD/types/supertest) from 2.0.16 to 6.0.2.
- [Release notes](https://github.com/DefinitelyTyped/DefinitelyTyped/releases)
- [Commits](https://github.com/DefinitelyTyped/DefinitelyTyped/commits/HEAD/types/supertest)

---
updated-dependencies:
- dependency-name: "@types/supertest"
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

packages/server/package.json

@@ -44,7 +44,7 @@
         "@sveltejs/kit": "1.21.0",
         "@types/body-parser": "^1.19.2",
         "@types/express": "^4.17.17",
-        "@types/supertest": "^2.0.12",
+        "@types/supertest": "^6.0.2",
         "@zenstackhq/testtools": "workspace:*",
         "body-parser": "^1.20.2",
         "decimal.js": "^10.4.2",