build(deps): bump dompurify from 1.0.11 to 2.0.17

Bumps [dompurify](https://github.com/cure53/DOMPurify) from 1.0.11 to 2.0.17.
- [Release notes](https://github.com/cure53/DOMPurify/releases)
- [Commits](cure53/DOMPurify@1.0.11...2.0.17)

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

package.json

@@ -17,7 +17,7 @@
     "aplayer": "^1.10.1",
     "axios": "^0.19.0",
     "cross-env": "^5.2.0",
-    "dompurify": "^1.0.11",
+    "dompurify": "^2.0.17",
     "gravatar": "^1.8.0",
     "highlight.js": "^9.15.8",
     "koa": "^2.6.2",