Bump chart.js from 2.9.3 to 2.9.4

Bumps [chart.js](https://github.com/chartjs/Chart.js) from 2.9.3 to 2.9.4.
- [Release notes](https://github.com/chartjs/Chart.js/releases)
- [Commits](https://github.com/chartjs/Chart.js/compare/v2.9.3...v2.9.4)

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

package.json

@@ -26,7 +26,7 @@
     },
     "dependencies": {
         "@babel/plugin-proposal-class-properties": "^7.10.4",
-        "chart.js": "^2.9.3",
+        "chart.js": "^2.9.4",
         "csv-file-validator": "^1.8.0",
         "js-cookie": "^2.2.1",
         "react-bootstrap": "^1.3.0",