Prepare for v3.9.1 release (#7686)

CHANGELOG.md

@@ -1,6 +1,24 @@
 CHANGELOG
 =========
 
+## 3.9.1 (2021-07-29)
+
+### Bug Fixes
+
+- [cli] - Respect provider aliases
+  [#7166](https://github.com/pulumi/pulumi/pull/7166)
+
+- [cli] - `pulumi stack ls` now returns all accessible stacks (removing
+  earlier cap imposed by the httpstate backend).
+  [#3620](https://github.com/pulumi/pulumi/issues/3620)
+
+- [sdk/go] - Fix panics caused by logging from `ApplyT`, affecting
+  `pulumi-docker` and potentially other providers
+  [#7661](https://github.com/pulumi/pulumi/pull/7661)
+
+- [sdk/python] - Handle unknown results from methods.
+  [#7677](https://github.com/pulumi/pulumi/pull/7677)
+
 ## 3.9.0 (2021-07-28)
 
 ### Improvements