minor #115 Prepare the 2.2.0 release (derrabus)

This PR was merged into the 2.2-dev branch.

Discussion
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Prepare the 2.2.0 release

I'd like to create a new release today, if you agree.

Commits
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99ddcaa Prepare the 2.2.0 release

Author: derrabus

CHANGELOG.md

@@ -1,10 +1,11 @@
 CHANGELOG
 =========
 
-# 2.2.0 (TBA)
+# 2.2.0 (2023-04-21)
 
 * Drop support for Symfony 4
 * Bump minimum version of PHP to 7.2
+* Support version 2 of the psr/http-message contracts
 
 # 2.1.3 (2022-09-05)