Bump eslint from 6.8.0 to 7.1.0

Bumps [eslint](https://github.com/eslint/eslint) from 6.8.0 to 7.1.0.
- [Release notes](https://github.com/eslint/eslint/releases)
- [Changelog](https://github.com/eslint/eslint/blob/master/CHANGELOG.md)
- [Commits](https://github.com/eslint/eslint/compare/v6.8.0...v7.1.0)

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

package.json

@@ -82,7 +82,7 @@
     "concat-files": "^0.1.1",
     "d3": "~5.15.0",
     "editor-layer-index": "github:osmlab/editor-layer-index#gh-pages",
-    "eslint": "^6.3.0",
+    "eslint": "^7.1.0",
     "gaze": "^1.1.3",
     "glob": "^7.1.0",
     "happen": "^0.3.1",