plugins/notify: allow raw for stages

Fix type of `plugins.notify.settings.stages` to allow to pass raw lua
code.

Change-Id: I9d7c24d42b66150ed6f1a2d3710a1a89594f489c

Author: ein-shved

plugins/by-name/notify/default.nix

@@ -31,15 +31,15 @@ lib.nixvim.plugins.mkNeovimPlugin {
       Max number of lines for a message.
     '';
     stages =
-      defaultNullOpts.mkNullable
+      defaultNullOpts.mkNullableWithRaw
         (
           with types;
           either (enum [
             "fade"
             "slide"
             "fade_in_slide_out"
             "static"
-          ]) (listOf str)
+          ]) (listOf (types.maybeRaw str))
         )
         "fade_in_slide_out"
         ''