chore: update changelog for version 3.7.1 (#13446)

Co-authored-by: Vítor De Araújo <[email protected]>

Author: gnufede

CHANGELOG.md

@@ -2,6 +2,18 @@
 
 Changelogs for versions not listed here can be found at https://github.com/DataDog/dd-trace-py/releases
 
+---
+
+## 3.7.1
+
+
+### Bug Fixes
+
+- CI Visibility
+  - Resolves an issue where pytest-xdist would not exit with the proper status code if ATR was enabled.
+  - Resolves an issue where ddtrace pytest plugin used with xdist would report test suites as failing even when all tests pass.
+
+
 ---
 
 ## 2.21.8