Add changelog for v3.4.1 release (hashicorp#350)

* Add changelog (hashicorp#346)

* Altering changelog entry from note to bug fix (hashicorp#346)

Author: bendbennett

.changes/unreleased/BUG FIXES-20231121-064539.yaml

@@ -0,0 +1,6 @@
+kind: BUG FIXES
+body: 'data-source/http: Includes update to go-retryablehttp fixing preservation of
+  request body on temporary redirects or re-established HTTP/2 connections'
+time: 2023-11-21T06:45:39.749197Z
+custom:
+  Issue: "346"