chore(deps): update dependency serverless-webpack to v5.15.0

Author: renovate[bot]

package.json

@@ -107,7 +107,7 @@
     "serverless-domain-manager": "2.6.13",
     "serverless-offline": "4.10.6",
     "serverless-plugin-aws-alerts": "1.7.5",
-    "serverless-webpack": "5.9.1",
+    "serverless-webpack": "5.15.0",
     "sinon": "7.5.0",
     "sinon-chai": "3.7.0",
     "webpack": "4.47.0",