build(deps-dev): bump supertest from 6.1.3 to 6.3.4

Bumps [supertest](https://github.com/ladjs/supertest) from 6.1.3 to 6.3.4.
- [Release notes](https://github.com/ladjs/supertest/releases)
- [Commits](forwardemail/supertest@v6.1.3...v6.3.4)

---
updated-dependencies:
- dependency-name: supertest
  dependency-version: 6.3.4
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

package.json

@@ -22,7 +22,7 @@
     "express": "4.17.1",
     "mocha": "9.1.1",
     "nyc": "15.1.0",
-    "supertest": "6.1.3"
+    "supertest": "6.3.4"
   },
   "files": [
     "lib/index.js",