chore: remove unused @serverless/utils dependency (#754)

The package is not imported anywhere in the codebase. Removing it also
eliminates the decompress-tar Zip Slip vulnerability (SNYK-JS-DECOMPRESSTAR-559095)
that was pulled in transitively through @serverless/utils.

Closes #753

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: VirtueMe

package-lock.json

@@ -42,7 +42,6 @@
   },
   "dependencies": {
     "@osls/compose": "^1.4.0",
-    "@serverless/utils": "^6.7.0",
     "asl-validator": "^3.11.0",
     "bluebird": "^3.4.0",
     "chalk": "^4.1.2",