build(deps): bump libphonenumber-js in /build/frontend-legacy

Bumps [libphonenumber-js](https://gitlab.com/catamphetamine/libphonenumber-js) from 1.12.29 to 1.12.31.
- [Changelog](https://gitlab.com/catamphetamine/libphonenumber-js/blob/master/CHANGELOG.md)
- [Commits](https://gitlab.com/catamphetamine/libphonenumber-js/compare/v1.12.29...v1.12.31)

---
updated-dependencies:
- dependency-name: libphonenumber-js
  dependency-version: 1.12.31
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

build/frontend-legacy/package-lock.json

@@ -69,7 +69,7 @@
     "jquery": "~3.7",
     "jquery-ui": "1.14.1",
     "jquery-ui-dist": "^1.13.3",
-    "libphonenumber-js": "^1.12.29",
+    "libphonenumber-js": "^1.12.31",
     "lodash": "^4.17.21",
     "marked": "^17.0.1",
     "moment": "^2.30.1",