Bump dompurify from 2.2.8 to 2.2.9

Bumps [dompurify](https://github.com/cure53/DOMPurify) from 2.2.8 to 2.2.9.
- [Release notes](https://github.com/cure53/DOMPurify/releases)
- [Commits](cure53/DOMPurify@2.2.8...2.2.9)

---
updated-dependencies:
- dependency-name: dompurify
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

package-lock.json

@@ -50,7 +50,7 @@
     "css-vars-ponyfill": "^2.3.2",
     "davclient.js": "git+https://github.com/owncloud/davclient.js.git#0.2.1",
     "debounce": "^1.2.0",
-    "dompurify": "^2.2.8",
+    "dompurify": "^2.2.9",
     "escape-html": "^1.0.3",
     "handlebars": "^4.7.7",
     "jcrop": "git+https://github.com/ChristophWurst/Jcrop.git#v0.9.12-npm3",