chore: change codeowners to dragonfly2's maintainers and reviewers
# standard @username or @org/team-name format. You can also refer to a user by an
# email address that has been added to their GitHub account, for example user@example.com
-.github/* @dragonflyoss/dragonfly-maintainers
+.github/* @dragonflyoss/dragonfly2-maintainers
-* @dragonflyoss/dragonfly-reviewer
+* @dragonflyoss/dragonfly2-reviewers
