Update CODEOWNERS

Author: clarkd

.github/CODEOWNERS

@@ -1,7 +1,7 @@
 # Root files
-/*.md                @squaredup
-/LICENSE             @squaredup
-/.github/*           @squaredup
+/*.md                @squaredup/community-moderators
+/LICENSE             @squaredup/community-moderators
+/.github/*           @squaredup/community-moderators
 
 # Request review from original author
 plugins/DigiCert/*  @shaswot77
@@ -20,4 +20,4 @@ plugins/TransportForLondon/*  @clarkd
 
 
 # Fallback – if a plugin has no specified author
-plugins/* @squaredup
+plugins/* @squaredup/community-moderators