Prepare release notes

Signed-off-by: Mathias L. Baumann <[email protected]>

Author: Marenz

RELEASE_NOTES.md

@@ -1,9 +1,5 @@
 # Frequenz Dispatch Client Library Release Notes
 
-## Summary
-
-<!-- Here goes a general summary of what this release is about -->
-
 ## Upgrading
 
 * An API key for authorization must now be passed to the `DispatchClient`.
@@ -12,7 +8,3 @@
 ## New Features
 
 * TLS is now enabled by default for the CLI client.
-
-## Bug Fixes
-
-<!-- Here goes notable bug fixes that are worth a special mention or explanation -->