fix(deps): update dependency rehype-document to v7 (#21)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

package.json

@@ -49,7 +49,7 @@
     "minimist": "^1.2.7",
     "recursive-readdir-files": "^2.3.0",
     "rehype-autolink-headings": "^7.0.0",
-    "rehype-document": "^6.1.0",
+    "rehype-document": "^7.0.0",
     "rehype-parse": "^8.0.4",
     "rehype-raw": "^6.1.1",
     "rehype-rewrite": "^3.0.6",