Merge pull request #52 from unasuke/update-invite-link-20250901

Update slack invitation link

Author: unasuke

_config.yml

@@ -20,4 +20,4 @@ twitter:
   card: summary_large_image
   username: ruby-jp
 
-slack_invite_link: https://join.slack.com/t/ruby-jp/shared_invite/zt-2yv9r07x3-8_VVdu_ycc9ZV9gXg7hYZQ
+slack_invite_link: https://join.slack.com/t/ruby-jp/shared_invite/zt-3clxgbp9t-UMujLz3ey2_t69p6nxkUFw