adjust permissions for docs files (#428)

Author: rkoron007

.github/CODEOWNERS

@@ -12,3 +12,6 @@
 /website/data/          @hashicorp/team-docs-packer-and-terraform @hashicorp/terraform-devex
 /website/public/        @hashicorp/team-docs-packer-and-terraform @hashicorp/terraform-devex
 /website/content/       @hashicorp/team-docs-packer-and-terraform @hashicorp/terraform-devex
+/website/docs/          @hashicorp/team-docs-packer-and-terraform @hashicorp/terraform-devex
+/website/img/           @hashicorp/team-docs-packer-and-terraform @hashicorp/terraform-devex
+/website/README.md      @hashicorp/team-docs-packer-and-terraform @hashicorp/terraform-devex