Allow Epic Link to be made required

Currently, it's possible to make Epic Link a required field by unlocking the field via SQL query, as described here: https://confluence.atlassian.com/jirakb/how-to-unlock-a-locked-field-779158866.html, and then clicking the Required link in the field configuration. However, any subsequent upgrade of the Jira software will switch it back to being optional again.

The recommended approach from Atlassian for making Epic Link required is to do so via a workflow validation rule. However, this is less than optimal for two reasons:

1. Default behavior in Jira is that each project gets its own workflow, meaning that each of potentially dozens to hundreds of workflows must be modified to add a validator. By contrast, projects default to using a single field configuration, so there are usually very few of these to modify to make a field required in the conventional way.
2. Fields made required via workflow validator do not appear as required (red asterisk) when viewing the form, so users do not have the right expectations until they receive an error on submitting it.

My suggestion is to allow Epic Link to be made required like any other field, persisting across Jira software updates, and ideally without requiring direct SQL queries to unlock it first.