Bump bitcoinjs-lib from 6.0.1 to 6.0.2 in /backend

Bumps [bitcoinjs-lib](https://github.com/bitcoinjs/bitcoinjs-lib) from 6.0.1 to 6.0.2.
- [Release notes](https://github.com/bitcoinjs/bitcoinjs-lib/releases)
- [Changelog](https://github.com/bitcoinjs/bitcoinjs-lib/blob/master/CHANGELOG.md)
- [Commits](https://github.com/bitcoinjs/bitcoinjs-lib/compare/v6.0.1...v6.0.2)

---
updated-dependencies:
- dependency-name: bitcoinjs-lib
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

backend/package.json

@@ -35,7 +35,7 @@
     "@mempool/electrum-client": "^1.1.7",
     "@types/node": "^16.11.41",
     "axios": "~0.27.2",
-    "bitcoinjs-lib": "6.0.1",
+    "bitcoinjs-lib": "6.0.2",
     "crypto-js": "^4.0.0",
     "express": "^4.18.0",
     "fast-xml-parser": "^4.0.9",