[Documentation] The 4.12 docs on `Disabling Prototype Extensions` are not updated according to `RFC: Deprecate array prototype extensions #848`

[johanrd]

📙 Describe the Issue

The 4.12 docs on Disabling Prototype Extensions are not updated according to RFC: Deprecate array prototype extensions #848

🔬 Minimal Reproduction

From the Ember 4.12.0 docs on Disabling Prototype Extensions:

By default, Ember.js will extend the prototypes of native JavaScript arrays to implement the Ember.Enumerable, Ember.MutableEnumerable, Ember.MutableArray and Ember.Array interfaces. This polyfills ECMAScript 5 array methods in browsers that do not implement them, adds convenience methods and properties to built-in arrays, and makes array mutations observable.

🤔 Expected Behavior

No longer mention that ember by default extends the prototypes of native JavaScript arrays to implement the Ember.Enumerable, Ember.MutableEnumerable, Ember.MutableArray and Ember.Array interfaces.

Perhaps also mention in the docs of the MutableArray class that ember no longer has Array prototype extension enabled by default?

[kategengler]

This RFC has not yet been implemented. You can track progress here emberjs/rfcs#1020