Add changelog for 3.6.3-RC2

Author: WojciechMazur

changelogs/3.6.3-RC2.md

@@ -0,0 +1,24 @@
+# Backported fixes
+
+- Fix: update `scala-cli.jar` path [#22274](http://github.com/scala/scala3/pull/22274)
+- Nowarn extension matching nonpublic member [#22276](http://github.com/scala/scala3/pull/22276)
+- Limit exposure to ConcurrentModificationException when sys props are replaced or mutated [#22275](http://github.com/scala/scala3/pull/22275)
+- Refactor: Improve Given search preference warning [#22273](http://github.com/scala/scala3/pull/22273)
+- Fix layout of released SDK archives, restore intermiediete top-level directory [#22272](http://github.com/scala/scala3/pull/22272)
+- REPL: JLine: follow recommendation to use JNI, not JNA; also JLine 3.27.1 (was 3.27.0) [#22271](http://github.com/scala/scala3/pull/22271)
+
+# Contributors
+
+Thank you to all the contributors who made this release possible 🎉
+
+According to `git shortlog -sn --no-merges 3.6.3-RC1..3.6.3-RC2` these are:
+
+```
+     4  Wojciech Mazur
+     2  João Ferreira
+     2  Seth Tisue
+     2  Som Snytt
+     1  Eugene Yokota
+     1  Hamza Remmal
+     1  Rui Chen
+```