build(deps): bump ajv from 6.12.0 to 6.12.6

Bumps [ajv](https://github.com/ajv-validator/ajv) from 6.12.0 to 6.12.6.
- [Release notes](https://github.com/ajv-validator/ajv/releases)
- [Commits](ajv-validator/ajv@v6.12.0...v6.12.6)

---
updated-dependencies:
- dependency-name: ajv
  dependency-type: indirect
...

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

Author: dependabot[bot]

yarn.lock

@@ -803,9 +803,9 @@ acorn@^3.1.0, acorn@^4.0.4, acorn@^7.1.1, acorn@~4.0.2:
   integrity sha512-add7dgA5ppRPxCFJoAGfMDi7PIBXq1RtGo7BhbLaxwrXPOmw8gq48Y9ozT01hUKy9byMjlR20EJhu5zlkErEkg==
 
 ajv@^6.5.5:
-  version "6.12.0"
-  resolved "https://registry.yarnpkg.com/ajv/-/ajv-6.12.0.tgz#06d60b96d87b8454a5adaba86e7854da629db4b7"
-  integrity sha512-D6gFiFA0RRLyUbvijN74DWAjXSFxWKaWP7mldxkVhyhAV3+SWA9HEJPHQ2c9soIeTFJqcSdFDGFgdqs1iUU2Hw==
+  version "6.12.6"
+  resolved "https://registry.yarnpkg.com/ajv/-/ajv-6.12.6.tgz#baf5a62e802b07d977034586f8c3baf5adf26df4"
+  integrity sha512-j3fVLgvTo527anyYyJOGTYJbG+vnnQYvE0m5mmkc1TK+nxAppkCLMIL0aZ4dblVCNoGShhm+kzE4ZUykBoMg4g==
   dependencies:
     fast-deep-equal "^3.1.1"
     fast-json-stable-stringify "^2.0.0"