doc: clarify removal of experimental API does not require a deprecation

PR-URL: nodejs#55746
Reviewed-By: Moshe Atlow <[email protected]>
Reviewed-By: Chengzhong Wu <[email protected]>
Reviewed-By: Gireesh Punathil <[email protected]>
Reviewed-By: Ulises Gascón <[email protected]>
Reviewed-By: Luigi Pinca <[email protected]>

Author: aduh95

doc/api/documentation.md

@@ -44,6 +44,9 @@ The stability indexes are as follows:
 >   still occur in response to user feedback. We encourage user testing and
 >   feedback so that we can know that this feature is ready to be marked as
 >   stable.
+>
+> Experimental features leave the experimental status typically either by
+> graduating to stable, or are removed without a deprecation cycle.
 
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