If you change name of "Epic" issue type, epic related functions does not work properly

Description

There is no way to detect which issue type is epic other than its name. If a customer renames "Epic" to something else this breaks our isEpic checks.
We can add a new setting, which allows customer to specify which issue type is actually an Epic. Note that customers still need to choose actual Epic issue type, they can't arbitrarily choose any issue type as epic. Because epic has special fields associated with it.

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Fixed

Priority

Major

Assignee

Deniz Oğuz

Reporter

Deniz Oğuz

Affects versions

None

Fix versions

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