CHANGELOG.md: add scorecard changes (#1443)

* CHANGELOG.md: add scorecard changes

Author: AlexNPavel

CHANGELOG.md

@@ -7,6 +7,7 @@
 - Unify CLI debug logging under a global `--verbose` flag ([#1361](https://github.com/operator-framework/operator-sdk/pull/1361))
 - [Go module](https://github.com/golang/go/wiki/Modules) support by default for new Go operators and during Ansible and Helm operator migration. The dependency manager used for a new operator can be explicitly specified for new operators through the `--dep-manager` flag, available in [`operator-sdk new`](https://github.com/operator-framework/operator-sdk/blob/master/doc/sdk-cli-reference.md#new) and [`operator-sdk migrate`](https://github.com/operator-framework/operator-sdk/blob/master/doc/sdk-cli-reference.md#migrate). `dep` is still available through `--dep-manager=dep`. ([#1001](https://github.com/operator-framework/operator-sdk/pull/1001))
 - New optional flag `--custom-api-import` for [`operator-sdk add controller`](https://github.com/operator-framework/operator-sdk/blob/master/doc/sdk-cli-reference.md#controller) to specify that the new controller reconciles a built-in or external Kubernetes API, and what import path and identifier it should have. ([#1344](https://github.com/operator-framework/operator-sdk/pull/1344))
+- Operator Scorecard plugin support ([#1379](https://github.com/operator-framework/operator-sdk/pull/1379)). Documentation for the scorecard plugins API will be added in PR [#1433](https://github.com/operator-framework/operator-sdk/pull/1433).
 
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