Bump d3 from 6.5.0 to 6.6.0

Bumps [d3](https://github.com/d3/d3) from 6.5.0 to 6.6.0.
- [Release notes](https://github.com/d3/d3/releases)
- [Changelog](https://github.com/d3/d3/blob/master/CHANGES.md)
- [Commits](https://github.com/d3/d3/compare/v6.5.0...v6.6.0)

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

package.json

@@ -86,7 +86,7 @@
     "cldr-localenames-full": "37.0.0",
     "colors": "^1.1.2",
     "concat-files": "^0.1.1",
-    "d3": "~6.5.0",
+    "d3": "~6.6.0",
     "editor-layer-index": "github:osmlab/editor-layer-index#gh-pages",
     "eslint": "^7.1.0",
     "gaze": "^1.1.3",