chore(deps): update dependency rehype-sanitize to v6

Author: renovate[bot]

package-lock.json

@@ -59,7 +59,7 @@
     "react-test-renderer": "^17.0.0",
     "rehype-katex": "^5.0.0",
     "rehype-raw": "^5.0.0",
-    "rehype-sanitize": "^4.0.0",
+    "rehype-sanitize": "^6.0.0",
     "remark-gfm": "^1.0.0",
     "remark-math": "^4.0.0",
     "tsdx": "^0.14.0",