Prepare release 3.3.4

Author: ste93cry

CHANGELOG.md

@@ -2,8 +2,11 @@
 
 ## Unreleased
 
+## 3.3.4 (2021-11-08)
+
 - Avoid overwriting the error level set by the user on the event when capturing an `ErrorException` exception (#1251)
 - Allow installing the project alongside Symfony `6.x` components (#1257)
+- Run the test suite against PHP `8.1` (#1245)
 
 ## 3.3.3 (2021-10-04)