chore(deps-dev): bump aegir from 19.0.5 to 20.6.0

Bumps [aegir](https://github.com/ipfs/aegir) from 19.0.5 to 20.6.0.
- [Release notes](https://github.com/ipfs/aegir/releases)
- [Changelog](https://github.com/ipfs/aegir/blob/master/CHANGELOG.md)
- [Commits](https://github.com/ipfs/aegir/compare/v19.0.5...v20.6.0)

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

package.json

@@ -34,7 +34,7 @@
     "secp256k1": "^3.6.2"
   },
   "devDependencies": {
-    "aegir": "^19.0.5",
+    "aegir": "^20.6.0",
     "benchmark": "^2.1.4",
     "chai": "^4.2.0",
     "dirty-chai": "^2.0.1",