Bump convict from 6.2.2 to 6.2.3 in /webapp

Bumps [convict](https://github.com/mozilla/node-convict) from 6.2.2 to 6.2.3.
- [Release notes](https://github.com/mozilla/node-convict/releases)
- [Changelog](https://github.com/mozilla/node-convict/blob/master/CHANGELOG.md)
- [Commits](mozilla/node-convict@v6.2.2...v6.2.3)

---
updated-dependencies:
- dependency-name: convict
  dependency-type: direct:production
...

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

webapp/package.json

@@ -39,7 +39,7 @@
     "bitcoinjs-lib": "^5.2.0",
     "bootstrap": "^4.6.0",
     "comma-number": "^2.1.0",
-    "convict": "^6.2.1",
+    "convict": "^6.2.3",
     "crypto-js": "^4.1.1",
     "http-status-codes": "^2.2.0",
     "is-electron": "^2.2.1",