update changelog for v0.4.0

Author: Phil Varner

CHANGELOG.md

@@ -4,6 +4,10 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## [Unreleased] - TBD
+
+None
+
 ## [v0.4.0] - 2022-06-08
 
 ### Added
@@ -201,6 +205,7 @@ are in a single HTTP session, handle pagination and respects conformance
 
 Initial release.
 
+[Unreleased]: <https://github.com/stac-utils/pystac-client/compare/v0.4.0...main>
 [v0.4.0]: <https://github.com/stac-utils/pystac-client/compare/v0.3.5...v0.4.0>
 [v0.3.5]: <https://github.com/stac-utils/pystac-client/compare/v0.3.4..v0.3.5>
 [v0.3.4]: <https://github.com/stac-utils/pystac-client/compare/v0.3.3..v0.3.4>

RELEASING.md

@@ -7,9 +7,8 @@
 4. Update [CHANGELOG.md](CHANGELOG.md).
    1. Add a new header under "Unreleased" with the new version and the date, e.g. `## [vX.Y.Z] - YYYY-MM-DD`.
    2. Audit the changelog section to ensure all changes are captured.
-   3. Add a new link reference at the bottom of the changelog with the new version.
+   3. Add a link reference for the new version after the Unreleased link reference at the bottom of the file.
       Follow the format from the previous version links.
-   4. Update the "Unreleased" link to reference your new version.
 5. (optional) Build the package locally and inspect its contents: `pip install build && python -m build`
 6. Open a pull request for your `release/vX.Y.Z` branch against the appropriate branch (either `main` or a version branch, e.g. `v0.3`).
    Include a section in the pull request description with the CHANGELOG contents for this version.