Update CHANGELOG.md

Author: radeksimko

CHANGELOG.md

@@ -7,6 +7,7 @@ ENHANCEMENTS:
 INTERNAL:
 
  - build(deps): bump github.com/creachadair/jrpc2 from 0.25.1 to 0.25.3 ([#649](https://github.com/hashicorp/terraform-ls/pull/649), [#650](https://github.com/hashicorp/terraform-ls/pull/650))
+ - build(deps): bump github.com/hashicorp/terraform-exec from 0.14.0 to 0.15.0 ([#664](https://github.com/hashicorp/terraform-ls/pull/664))
 
 ## 0.22.0 (16 September 2021)