Remove empty section from the release notes (#54)

This is to prepare for the release.

Author: llucax

RELEASE_NOTES.md

@@ -1,13 +1,5 @@
 # Frequenz Common API Release Notes
 
-## Summary
-
-<!-- Here goes a general summary of what this release is about -->
-
-## Upgrading
-
-<!-- Here goes notes on how to upgrade from previous versions, including deprecations and what they should be replaced with -->
-
 ## New Features
 
 * Added a new message named `Location`, representing the co-ordinates of a
@@ -18,7 +10,3 @@
 
 * Added a new variant `COMPONENT_CATEGORY_PRECHARGE_MODULE` to the
   `ComponentCategory` enum.
-
-## Bug Fixes
-
-<!-- Here goes notable bug fixes that are worth a special mention or explanation -->