Update changelog for v3.20.1 release
## Unreleased
-- Update the provider and tests to use Go 1.18.
-- Fix Helm Chart not working with Crossguard (#2057)
+## 3.20.1 (July 19, 2022)
+
+- Update the provider and tests to use Go 1.18. (https://github.com/pulumi/pulumi-kubernetes/issues/2073)
+- Fix Helm Chart not working with Crossguard (https://github.com/pulumi/pulumi-kubernetes/issues/2057)
- Handle ignoreChanges for Server-Side Apply mode (https://github.com/pulumi/pulumi-kubernetes/pull/2074)
## 3.20.0 (July 12, 2022)
