build(deps): bump ajv from 8.17.1 to 8.18.0 in /backend (#238)

Bumps [ajv](https://github.com/ajv-validator/ajv) from 8.17.1 to 8.18.0.
- [Release notes](https://github.com/ajv-validator/ajv/releases)
- [Commits](https://github.com/ajv-validator/ajv/compare/v8.17.1...v8.18.0)

---
updated-dependencies:
- dependency-name: ajv
  dependency-version: 8.18.0
  dependency-type: indirect
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

backend/package-lock.json

@@ -2348,9 +2348,9 @@
       "license": "MIT"
     },
     "node_modules/ajv": {
-      "version": "8.17.1",
-      "resolved": "https://registry.npmjs.org/ajv/-/ajv-8.17.1.tgz",
-      "integrity": "sha512-B/gBuNg5SiMTrPkC+A2+cW0RszwxYmn6VYxB/inlBStS5nx6xHIt/ehKRhIMhqusl7a8LjQoZnjCs5vhwxOQ1g==",
+      "version": "8.18.0",
+      "resolved": "https://registry.npmjs.org/ajv/-/ajv-8.18.0.tgz",
+      "integrity": "sha512-PlXPeEWMXMZ7sPYOHqmDyCJzcfNrUr3fGNKtezX14ykXOEIvyK81d+qydx89KY5O71FKMPaQ2vBfBFI5NHR63A==",
       "license": "MIT",
       "dependencies": {
         "fast-deep-equal": "^3.1.3",