Bump ajv from 6.12.5 to 6.12.6

Bumps [ajv](https://github.com/ajv-validator/ajv) from 6.12.5 to 6.12.6.
- [Release notes](https://github.com/ajv-validator/ajv/releases)
- [Commits](ajv-validator/ajv@v6.12.5...v6.12.6)

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

package.json

@@ -35,7 +35,7 @@
     "test:ci": "jest --runInBand"
   },
   "dependencies": {
-    "ajv": "^6.12.5",
+    "ajv": "^6.12.6",
     "ajv-errors": "^1.0.1",
     "chalk": "^4.1.0",
     "cosmiconfig": "^6.0.0",