chore:(deps): bump chart.js from 2.9.3 to 2.9.4 in /explorer (#13194)

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[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

explorer/package-lock.json

@@ -5507,9 +5507,9 @@
       "integrity": "sha512-mT8iDcrh03qDGRRmoA2hmBJnxpllMR+0/0qlzjqZES6NdiWDcZkCNAk4rPFZ9Q85r27unkiNNg8ZOiwZXBHwcA=="
     },
     "chart.js": {
-      "version": "2.9.3",
-      "resolved": "https://registry.npmjs.org/chart.js/-/chart.js-2.9.3.tgz",
-      "integrity": "sha512-+2jlOobSk52c1VU6fzkh3UwqHMdSlgH1xFv9FKMqHiNCpXsGPQa/+81AFa+i3jZ253Mq9aAycPwDjnn1XbRNNw==",
+      "version": "2.9.4",
+      "resolved": "https://registry.npmjs.org/chart.js/-/chart.js-2.9.4.tgz",
+      "integrity": "sha512-B07aAzxcrikjAPyV+01j7BmOpxtQETxTSlQ26BEYJ+3iUkbNKaOJ/nDbT6JjyqYxseM0ON12COHYdU2cTIjC7A==",
       "requires": {
         "chartjs-color": "^2.1.0",
         "moment": "^2.10.2"

explorer/package.json

@@ -25,7 +25,7 @@
     "bootstrap": "^4.5.3",
     "bs58": "^4.0.1",
     "chai": "^4.2.0",
-    "chart.js": "^2.9.3",
+    "chart.js": "^2.9.4",
     "classnames": "2.2.6",
     "humanize-duration-ts": "^2.1.1",
     "node-sass": "^4.14.1",