Update changelog for v2.7.0 release
## HEAD (Unreleased)
+## 2.7.0 (November 12, 2020)
+
- Add support for previewing Create and Update operations for API servers that support dry-run (https://github.com/pulumi/pulumi-kubernetes/pull/1355)
- Fix panic introduced in #1355 (https://github.com/pulumi/pulumi-kubernetes/pull/1368)
-- Add ready attribute to await Helm charts (https://github.com/pulumi/pulumi-kubernetes/pull/1364)
+- (NodeJS) Add ready attribute to await Helm charts (https://github.com/pulumi/pulumi-kubernetes/pull/1364)
- Update Helm to v3.4.0 and client-go to v1.19.2 (https://github.com/pulumi/pulumi-kubernetes/pull/1360)
- Update Helm to v3.4.1 and client-go to v1.19.3 (https://github.com/pulumi/pulumi-kubernetes/pull/1365)
- Fix panic when provider is given kubeconfig as an object instead of string (https://github.com/pulumi/pulumi-kubernetes/pull/1373)
