deps: bump @multiformats/mafmt from 11.1.2 to 12.1.6

Bumps [@multiformats/mafmt](https://github.com/multiformats/js-mafmt) from 11.1.2 to 12.1.6.
- [Release notes](https://github.com/multiformats/js-mafmt/releases)
- [Changelog](https://github.com/multiformats/js-mafmt/blob/master/CHANGELOG.md)
- [Commits](multiformats/js-mafmt@v11.1.2...v12.1.6)

---
updated-dependencies:
- dependency-name: "@multiformats/mafmt"
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

package.json

@@ -145,7 +145,7 @@
     "docs": "aegir docs"
   },
   "dependencies": {
-    "@multiformats/mafmt": "^11.0.3",
+    "@multiformats/mafmt": "^12.1.6",
     "@multiformats/multiaddr": "^11.0.0",
     "iso-url": "^1.1.3",
     "multiformats": "^11.0.0",