fix: set codegenConfig key to macos (microsoft#2822)

## Summary:

Per suggestion from @tido64 , set this key to `macos` so codegen doesn't
complain about duplicate ios modules. Not sure if this fix holds if we
want to use react-native-macos for iOS or visionOS, but time will tell.

## Test Plan:

CI should pass

Author: Saadnajmi

packages/react-native/package.json

@@ -202,7 +202,7 @@
       {
         "name": "FBReactNativeSpec",
         "type": "all",
-        "ios": {
+        "macos": {
           "modules": {
             "AccessibilityManager": {
               "unstableRequiresMainQueueSetup": true