fix: upgrade @loopback/core from 5.1.4 to 5.1.5

Snyk has created this PR to upgrade @loopback/core from 5.1.4 to 5.1.5.

See this package in npm:
https://www.npmjs.com/package/@loopback/core

See this project in Snyk:
https://app.snyk.io/org/minottic/project/15fa623e-9ad6-4182-ba0a-03235f8571b1?utm_source=github&utm_medium=referral&page=upgrade-pr

package.json

@@ -55,7 +55,7 @@
   ],
   "dependencies": {
     "@loopback/boot": "^6.1.5",
-    "@loopback/core": "^5.1.4",
+    "@loopback/core": "^5.1.5",
     "@loopback/repository": "^6.1.4",
     "@loopback/rest": "^13.1.5",
     "@loopback/rest-explorer": "^6.1.4",