DOC: changelog.md update for multidim drag

Author: aZira371

CHANGELOG.md

@@ -32,6 +32,7 @@ Attention: The newest changes should be on top -->
 
 ### Added
 
+- ENH: Add multi-dimensional drag coefficient support (Cd as function of M, Re, α) [#875](https://github.com/RocketPy-Team/RocketPy/pull/875)
 - ENH: Enable only radial burning [#815](https://github.com/RocketPy-Team/RocketPy/pull/815)
 - ENH: Add thrustcurve api integration to retrieve motor eng data [#870](https://github.com/RocketPy-Team/RocketPy/pull/870)
 - ENH: Custom Exception errors and messages [#285](https://github.com/RocketPy-Team/RocketPy/issues/285)