Update Philip Chimento's status to committer

https://bugs.webkit.org/show_bug.cgi?id=300745

Reviewed by Alex Christensen.

I have the countersigned committer agreement so it's time to update
contributors.json.

Canonical link: https://commits.webkit.org/301575@main

Author: ptomato

metadata/contributors.json

@@ -6762,7 +6762,8 @@
       "nicks" : [
          "pchimento",
          "ptomato"
-      ]
+      ],
+      "status" : "committer"
    },
    {
       "emails" : [