Prepare for next release

Author: brews

CHANGELOG.md

@@ -4,6 +4,9 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+
+
 ## [0.2.0] - 2022-09-16
 ### Changed
 - Remove mutable argument defaults to avoid gotchas. ([PR #44](https://github.com/ClimateImpactLab/dscim/pull/44), [@brews](https://github.com/brews))