Bump winston-loki from 6.1.3 to 6.1.4 in /backend

Bumps [winston-loki](https://github.com/JaniAnttonen/winston-loki) from 6.1.3 to 6.1.4.
- [Release notes](https://github.com/JaniAnttonen/winston-loki/releases)
- [Commits](JaniAnttonen/winston-loki@v6.1.3...v6.1.4)

---
updated-dependencies:
- dependency-name: winston-loki
  dependency-version: 6.1.4
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

backend/package-lock.json

@@ -35,7 +35,7 @@
     "prom-client": "^15.1.3",
     "tesseract.js": "^6.0.1",
     "winston": "^3.17.0",
-    "winston-loki": "^6.1.3",
+    "winston-loki": "^6.1.4",
     "zod": "^3.25.76"
   },
   "devDependencies": {