Remove cloud_license_enabled database column

After previously removing the guards that used the application
setting's cloud_license_enabled, the database column can be removed as
well.

Changelog: removed
MR: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/65541

db/post_migrate/20210706112800_remove_cloud_license_enabled_from_application_settings.rb

+# frozen_string_literal: true
+
+class RemoveCloudLicenseEnabledFromApplicationSettings < ActiveRecord::Migration[6.1]
+  include Gitlab::Database::MigrationHelpers
+
+  disable_ddl_transaction!
+
+  def up
+    with_lock_retries do
+      remove_column :application_settings, :cloud_license_enabled
+    end
+  end
+
+  def down
+    with_lock_retries do
+      add_column :application_settings, :cloud_license_enabled, :boolean, null: false, default: false
+    end
+  end
+end

db/schema_migrations/20210706112800

+5dd1596d0d6e6f5aa39cbf8a65be294650bead7a099cf50917b438cf75529257
\ No newline at end of file

db/structure.sql

@@ -9596,7 +9596,6 @@ CREATE TABLE application_settings (
     encrypted_cloud_license_auth_token text,
     encrypted_cloud_license_auth_token_iv text,
     secret_detection_revocation_token_types_url text,
-    cloud_license_enabled boolean DEFAULT false NOT NULL,
     disable_feed_token boolean DEFAULT false NOT NULL,
     personal_access_token_prefix text,
     rate_limiting_response_text text,