ci: bump winston from 3.14.2 to 3.15.0

Bumps [winston](https://github.com/winstonjs/winston) from 3.14.2 to 3.15.0.
- [Release notes](https://github.com/winstonjs/winston/releases)
- [Changelog](https://github.com/winstonjs/winston/blob/master/CHANGELOG.md)
- [Commits](winstonjs/winston@v3.14.2...v3.15.0)

---
updated-dependencies:
- dependency-name: winston
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

package.json

@@ -32,7 +32,7 @@
     "redoc-express": "^2.1.0",
     "serve-favicon": "^2.5.0",
     "swagger-stats": "^0.99.7",
-    "winston": "^3.14.2",
+    "winston": "^3.15.0",
     "yaml": "^2.5.1"
   },
   "devDependencies": {