Enable/disable Automation for Jira setting to show or hide this feature in your Jira instance.
To access this setting:
On your Jira dashboard menu Git ➜ Manage repositories.
On the sidebar, click General settings.
Under Jira workflow integrations section, enable/disable this setting according to your organization rules and policies.
For more information on this feature, see Git Integration + Automation for Jira.
More on general settings
Enable Automation for Jira general setting (this page)