refactor: Replace 'meta.ci' -> 'meta.ci.skip'

We need 'meta.ci' to be an attribute set for new CI features.

Change-Id: I83d04e2d74e42e49fe739b049ee4ba799f6d5d86
Reviewed-on: https://cl.tvl.fyi/c/depot/+/5007
Tested-by: BuildkiteCI
Reviewed-by: ezemtsov <eugene.zemtsov@gmail.com>
Reviewed-by: wpcarro <wpcarro@gmail.com>

users/wpcarro/boilerplate/typescript/default.nix

@@ -19,5 +19,5 @@ pkgs.stdenv.mkDerivation {
   '';
 
   # TODO(wpcarro): This doesn't build at all.
-  meta.ci = false;
+  meta.ci.skip = true;
 }

users/wpcarro/website/sandbox/contentful/default.nix

@@ -20,5 +20,5 @@ pkgs.stdenv.mkDerivation {
   '';
 
   # TODO(wpcarro): This doesn't build at all.
-  meta.ci = false;
+  meta.ci.skip = true;
 }