Add Terraform Core team as shared CODEOWNERS

.github/CODEOWNERS

@@ -2,12 +2,12 @@
 # More on CODEOWNERS files: https://help.github.com/en/github/creating-cloning-and-archiving-repositories/about-code-owners
 
 # Default owner
-* @hashicorp/team-ip-compliance
+* @hashicorp/team-ip-compliance @hashicorp/terraform-core
 
 # Add override rules below. Each line is a file/folder pattern followed by one or more owners.
 # Being an owner means those groups or individuals will be added as reviewers to PRs affecting
 # those areas of the code.
 # Examples:
 # /docs/  @docs-team
 # *.js    @js-team
-# *.go    @go-team
+# *.go    @go-team