chore(deps): bump loopback from 3.27.0 to 3.28.0 in /api-server

Bumps [loopback](https://github.com/strongloop/loopback) from 3.27.0 to 3.28.0.
- [Release notes](https://github.com/strongloop/loopback/releases)
- [Changelog](https://github.com/strongloop/loopback/blob/master/CHANGES.md)
- [Commits](https://github.com/strongloop/loopback/compare/v3.27.0...v3.28.0)

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

api-server/package.json

@@ -37,7 +37,7 @@
     "helmet-csp": "^2.10.0",
     "jsonwebtoken": "^8.5.1",
     "lodash": "^4.17.20",
-    "loopback": "^3.27.0",
+    "loopback": "^3.28.0",
     "loopback-boot": "^2.28.0",
     "loopback-connector-mongodb": "^4.2.0",
     "method-override": "^3.0.0",