[skip ci] Update CHANGELOG.md for release

Author: mdbenito

CHANGELOG.md

@@ -1,22 +1,22 @@
 # Changelog
 
-## Unreleased 🆕 New influence method, better docs and bugfixes 📚🐞
+## 0.9.0 🆕 New methods, better docs and bugfixes 📚🐞
 
 ### Added
 
-- New method: `NystroemSketchInfluence`
-  [PR #504](https://github.com/aai-institute/pyDVL/pull/504)
 - New method `MSR Banzhaf` with accompanying notebook, and new stopping
   criterion `RankCorrelation`
   [PR #520](https://github.com/aai-institute/pyDVL/pull/520)
+- New method: `NystroemSketchInfluence`
+  [PR #504](https://github.com/aai-institute/pyDVL/pull/504)
 - New preconditioned block variant of conjugate gradient
   [PR #507](https://github.com/aai-institute/pyDVL/pull/507)
 - Improvements to documentation: fixes, links, text, example gallery, LFS and
-  more. [PR #532](https://github.com/aai-institute/pyDVL/pull/532), 
+  more [PR #532](https://github.com/aai-institute/pyDVL/pull/532), 
   [PR #543](https://github.com/aai-institute/pyDVL/pull/543)
 - Glossary of data valuation and influence terms in the documentation
   [PR #537](https://github.com/aai-institute/pyDVL/pull/537
-- Documentation about writing notes for new features, changes or deprecations.
+- Documentation about writing notes for new features, changes or deprecations
   [PR #557](https://github.com/aai-institute/pyDVL/pull/557)
 
 ### Fixed