Add danger text to feature flag section of the Pointer Events blog post (facebook#4520)

* Add danger text to feature flag section of the Pointer Events blog post

As we get closer to enabling Pointer Events by default we want to ensure that people understand that utilizing these feature flags will cause breakages when we phase them out.

* Update website/blog/2022-12-13-pointer-events-in-react-native.md

Co-authored-by: Bartosz Kaszubowski <[email protected]>

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Co-authored-by: Luna <[email protected]>
Co-authored-by: Bartosz Kaszubowski <[email protected]>

Author: 3 people

website/blog/2022-12-13-pointer-events-in-react-native.md

@@ -106,6 +106,12 @@ Our Pointer Events implementation is still experimental but we’re interested i
 
 ### Enable Feature Flags
 
+:::danger
+
+Overriding the native feature flags below (such as `RCTConstants` and `ReactFeatureFlags`) is technically reaching into React Native's internals so doing so may break your setup soon as we are working to phase them out in order for us to roll Pointer Events out more broadly.
+
+:::
+
 :::note
 
 Pointer Events are only implemented for the [New Architecture (Fabric)](https://reactnative.dev/docs/the-new-architecture/use-app-template) and are only available for React Native 0.71+ which at the time of writing is a release candidate.