Bump bn.js from 5.1.2 to 5.1.3 in /token/js (#312)

Bumps [bn.js](https://github.com/indutny/bn.js) from 5.1.2 to 5.1.3.
- [Release notes](https://github.com/indutny/bn.js/releases)
- [Changelog](https://github.com/indutny/bn.js/blob/master/CHANGELOG.md)
- [Commits](https://github.com/indutny/bn.js/compare/v5.1.2...v5.1.3)

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

token/js/package-lock.json

@@ -2665,9 +2665,9 @@
       "dev": true
     },
     "bn.js": {
-      "version": "5.1.2",
-      "resolved": "https://registry.npmjs.org/bn.js/-/bn.js-5.1.2.tgz",
-      "integrity": "sha512-40rZaf3bUNKTVYu9sIeeEGOg7g14Yvnj9kH7b50EiwX0Q7A6umbvfI5tvHaOERH0XigqKkfLkFQxzb4e6CIXnA=="
+      "version": "5.1.3",
+      "resolved": "https://registry.npmjs.org/bn.js/-/bn.js-5.1.3.tgz",
+      "integrity": "sha512-GkTiFpjFtUzU9CbMeJ5iazkCzGL3jrhzerzZIuqLABjbwRaFt33I9tUdSNryIptM+RxDet6OKm2WnLXzW51KsQ=="
     },
     "boolbase": {
       "version": "1.0.0",