Remove unreleased changelog entry (#158)

CHANGELOG.md

@@ -1,8 +1,3 @@
-## [2.13.0] - 2023-07-17
-FEATURES:
-
-- Adds the new `launchdarkly_team_role_mapping` resource to manage the custom roles associated with a LaunchDarkly team. This is useful if the LaunchDarkly team is created and managed externally, such as via [Okta SCIM](https://docs.launchdarkly.com/home/account-security/okta/#using-okta-to-manage-launchdarkly-teams-with-scim). If you wish to create an manage the team using Terraform, we recommend using the [`launchdarkly_team` resource](https://registry.terraform.io/providers/launchdarkly/launchdarkly/latest/docs/resources/team) instead. [#152](https://github.com/launchdarkly/terraform-provider-launchdarkly/issues/152)
-
 ## [2.12.2] - 2023-06-28
 
 BUG FIXES: