Bump jstree from 3.3.8 to 3.3.9

Bumps [jstree](https://github.com/vakata/jstree) from 3.3.8 to 3.3.9.
- [Release notes](https://github.com/vakata/jstree/releases)
- [Commits](https://github.com/vakata/jstree/compare/3.3.8...3.3.9)

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

package.json

@@ -10,7 +10,7 @@
     "highlight.js": "^9.18.0",
     "jquery": "^3.4.1",
     "jquery-ui": "^1.12.1",
-    "jstree": "^3.3.8",
+    "jstree": "^3.3.9",
     "opensans-webkit": "^1.0.1",
     "popper.js": "^1.16.1",
     "snyk": "^1.290.2",