fix docs

book/src/SUMMARY.md

@@ -19,7 +19,6 @@
     - [Calling Ruby from Rust](./ruby/calling_script_from_rust.md)
     - [Interacting with bevy in callbacks](./ruby/interacting_with_bevy.md)
     - [Builtin types](./ruby/builtin_types.md)
-        - [Builtin variables](./ruby/builtin_variables.md)
   - [Rhai](./rhai/rhai.md)
     - [Installation](./rhai/installation.md)
     - [Hello World(TBD)]()

book/src/ruby/builtin_types.md

@@ -55,6 +55,8 @@ fn set_translation(
 
 ## Bevy::Entity
 
+`Bevy::Entity.current` is currently not available within promise callbacks.
+
 ### Constructor
 
 None - instances can only be acquired by using `Bevy::Entity.current`

book/src/ruby/builtin_variables.md

@@ -1,13 +1 @@
 # Builtin variables
-
-## entity
-
-Current entity that the script is atteched to can be retrieved by calling `Bevy::Entity.current`.
-It exposes `index` method that returns bevy entity index.
-It is useful for accessing entity's components from scripts.
-It can be used in the following way:
-```ruby
-puts("Current entity index: #{Bevy::Entity.current.index}")
-```
-
-`Bevy::Entity.current` variable is currently not available within promise callbacks.