[Security] Bump jquery from 2.2.4 to 3.4.0

Bumps [jquery](https://github.com/jquery/jquery) from 2.2.4 to 3.4.0. **This update includes security fixes.**
- [Release notes](https://github.com/jquery/jquery/releases)
- [Commits](https://github.com/jquery/jquery/compare/2.2.4...3.4.0)

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

package.json

@@ -20,7 +20,7 @@
     "flatpickr": "^4.5.7",
     "github-markdown-css": "^2.3.0",
     "ionicons": "~2.0",
-    "jquery": "^2.2.4",
+    "jquery": "^3.4.0",
     "jquery-minicolors": "^2.1.10",
     "jquery-serializeobject": "^1.0.0",
     "jquery-sparkline": "^2.4.0",