Prepare changelog for v17.0.0-rc.2

Author: RiotRobot

CHANGELOG.md

@@ -1,3 +1,6 @@
+Changes in [17.0.0-rc.2](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v17.0.0-rc.2) (2022-04-08)
+============================================================================================================
+
 Changes in [17.0.0-rc.1](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v17.0.0-rc.1) (2022-04-08)
 ============================================================================================================