Added IdentityServer directories to Auth ownership.

Author: trmartin4

.github/CODEOWNERS

@@ -37,6 +37,8 @@ util/Setup/** @bitwarden/dept-bre @bitwarden/team-platform-dev
 **/Auth @bitwarden/team-auth-dev
 bitwarden_license/src/Sso @bitwarden/team-auth-dev
 src/Identity @bitwarden/team-auth-dev
+src/Core/Identity @bitwarden/team-auth-dev
+src/Core/IdentityServer @bitwarden/team-auth-dev
 
 # Key Management team
 **/KeyManagement @bitwarden/team-key-management-dev