Remove redundant --repo flag from gh pr create command in README

Agent-Logs-Url: https://github.com/NextCommunity/NextCommunity.github.io/sessions/28279aa1-4b58-4759-9b5b-53e7ed008241

Co-authored-by: jbampton <418747+jbampton@users.noreply.github.com>

Author: Copilot

README.md

@@ -617,7 +617,6 @@ git push origin add-your-github-username
 
 ```bash
 gh pr create \
-  --repo NextCommunity/NextCommunity.github.io \
   --base main \
   --title "Add [Your Name] to directory" \
   --body "Fixes #213