fix: remove duplicated dead link from docs

spec/common-client-libs-sections.json

@@ -471,13 +471,6 @@
         "product": "auth",
         "type": "function"
       },
-      {
-        "id": "session",
-        "title": "Retrieve a session",
-        "slug": "auth-session",
-        "product": "auth",
-        "type": "function"
-      },
       {
         "id": "auth-update",
         "title": "Update a user",