FED-3249 Update docs about migrator companion codemod

doc/null_safety/null_safe_migration.md

@@ -51,9 +51,12 @@ dart pub global run over_react_codemod:null_safety_migrator_companion --yes-to-a
 ```
 
 This codemod will:
-- Add nullability hints to props/state that are defaulted/initialized in class components.
+- Add nullability hints to state mixin/class fields
   - These hints will cause defaulted/initialized values to be migrated as "late required". 
     See our [prop requiredness and nullability](#prop-requiredness-and-nullability) docs for more details on whether you should keep them required following the migration.
+  - All non-initialized state fields will have optional nullable hints.
+- Add nullable hints for callback ref types.
+- Add annotations to disable required prop validation for `connect` props. See [`connect` required props migration case](#wrapper-and-connected-components-and-required-props) for more info.
 
 #### Required props codemod
 
@@ -208,7 +211,7 @@ of the null safety and required props docs for instructions on how to handle the
 
 For connect, either:
 - Disable validation using the instructions linked above 
-    - Note: for now, this must be done manually, but we'll be adding a codemod to help do this automatically for `connect`: https://github.com/Workiva/over_react_codemod/issues/295
+    - Note: The [null safety migrator companion codemod](#companion-codemod) does this automatically for all `connect` props.
 - Refactor your component to instead utilize [OverReact Redux hooks](../over_react_redux_documentation.md#hooks), 
     which avoid this problem by accessing store data and dispatchers directly in the component as opposed to passing it in via props.