Document sqlite fix in changelog

Author: WhyNotHugo

CHANGELOG.rst

@@ -16,6 +16,8 @@ Version 0.20.0
 - Implement ``filter_hook`` for the HTTP storage.
 - Drop support for Python 3.7.
 - Add support for Python 3.12 and Python 3.13.
+- Properly close the status database after using. This especially affects tests,
+  where we were leaking a large amount of file descriptors.
 
 Version 0.19.3
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