Merge pull request #253 from npeltier/hlxignore

- remove root json,
- remove code coverage,
- generic rule for sidekick like nested json

Test URLs:
Before: https://main--cc--adobecom.hlx.live/?martech=off
After: https://hlxignore--cc--npeltier.hlx.page/?martech=off

.hlxignore

@@ -1,5 +1,8 @@
+*.json
+!*/**/*.json
 .*
 *.md
 LICENSE
 test/*
-!tools/sidekick/config.json
+web-test-runner.config.mjs
+codecov.yaml