Add changelog

Author: dagnir

.changes/next-release/bugfix-Apache5HTTPClient-2866d44.json

@@ -0,0 +1,6 @@
+{
+    "type": "bugfix",
+    "category": "Apache 5 HTTP Client",
+    "contributor": "",
+    "description": "Fixed an issue in the Apache 5 HTTP client where requests could fail with `\"Endpoint not acquired / already released\"`. These failures are now converted to retryable I/O errors."
+}