feat(site): allow string-width update

string-width@v6 uses Intl.Segmenter(), and
Firefox 125(Apr 16, 2024) added Intl.Segmenter()

relates to: #865

Author: frantic1048

renovate.json

@@ -12,10 +12,6 @@
     "postUpdateOptions": ["yarnDedupeHighest"],
     "reviewers": ["frantic1048"],
     "packageRules": [
-        {
-            "matchPackageNames": ["string-width"],
-            "enabled": false
-        },
         {
             "groupName": "linters and formatters",
             "automerge": true,