Update change-note wording

Co-authored-by: Aditya Sharad <6874315+adityasharad@users.noreply.github.com>

Author: RasmusWL

python/ql/lib/change-notes/2024-12-18-fastapi-request-modeling.md

@@ -1,4 +1,5 @@
 ---
 category: minorAnalysis
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-* Added modeling of `fastapi.Request`, which will improve taint-flow for users of FastAPI.
+* Added modeling of `fastapi.Request` and `starlette.requests.Request` as sources of untrusted input,
+  and modeling of tainted data flow out of these request objects.