Bump dompurify from 3.1.2 to 3.1.6

Bumps [dompurify](https://github.com/cure53/DOMPurify) from 3.1.2 to 3.1.6.
- [Release notes](https://github.com/cure53/DOMPurify/releases)
- [Commits](https://github.com/cure53/DOMPurify/compare/3.1.2...3.1.6)

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

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

package.json

@@ -30,7 +30,7 @@
     "bulma-prefers-dark": "^0.1.0-beta.1",
     "copy-to-clipboard": "^3.3.3",
     "dexie": "^4.0.1-beta.5",
-    "dompurify": "^3.0.6",
+    "dompurify": "^3.1.6",
     "eslint-config-standard-with-typescript": "^35.0.0",
     "eslint-plugin-svelte3": "^4.0.0",
     "flourite": "^1.3.0",