fix: create auto_repeat field only if docfield/custom field does not exist

[ruchamahabal]

Some Standard DocTypes already have an auto_repeat standard field. Checking Allow Auto Repeat breaks here, since it tries to create a custom field when a standard docfield already exists.

Fix: Create custom field only if standard docfield / custom field is not already present. This property is now enabled for such doctypes in frappe/erpnext#23776

[surajshetty3416]

@ruchamahabal can we move create_auto_repeat_custom_field_if_required outside fetch_to_customize because create_auto_repeat_custom_field_if_required is getting called unnecessarily on customize form load.

We can move it to save_customization.

[scmmishra]

@Mergifyio backport version-13-beta

[mergify]

Command backport version-13-beta: success

Backports have been created

• #11951 fix: create auto_repeat field only if docfield/custom field does not exist (bp #11827) has been created for branch version-13-beta