Remove CanCan v1 doc (#496)

Author: lsgunnlsgunn

modules/ROOT/nav.adoc

@@ -39,7 +39,7 @@
 ** xref:developers-guide:tutorials/custom-frontend.adoc[Customize the front-end]
 ** xref:developers-guide:tutorials/my-contacts.adoc[Add a stylesheet]
 ** xref:developers-guide:tutorials/intercanister-calls.adoc[Make inter-canister calls]
-** xref:developers-guide:tutorials/scalability-cancan.adoc[Create scalable apps]
+//** xref:developers-guide:tutorials/scalability-cancan.adoc[Create scalable apps]
 ** xref:developers-guide:tutorials/access-control.adoc[Add access control with identities]
 ** xref:developers-guide:tutorials/simple-cycles.adoc[Accept cycles from a wallet]