Docs: core actions reference

Signed-off-by: Solomon Hykes <solomon@dagger.io>

website/sidebars.js

@@ -100,7 +100,6 @@ module.exports = {
         "core-concepts/client",
         "core-concepts/secrets",
         "core-concepts/what-is-cue",
-        "core-concepts/dagger-cue",
         "core-concepts/cli-telemetry",
       ],
     },
@@ -111,6 +110,15 @@ module.exports = {
       collapsed: false,
       items: ["guides/container-images"],
     },
+    {
+      type: "category",
+      label: "References",
+      collapsible: false,
+      collapsed: false,
+      items: [
+        "references/core-actions-reference",
+      ],
+    },
     {
       type: "category",
       label: "Use Cases",