Allows to limit link to substring of issueLinkTextFormat

[baflo]

The full text of will be a link by default. If you want to limit it to substring(s), you can surround them with brackets, e.g [%key%] %summary% will only make %key% a link.

[stantler]

Hey, @baflo right now I have this issue link (%priority%) \[%key%\] %summary% and after your change actual link will be only in brackets. And I don't want it

Maybe it's better to introduce "expert" option, where user can input whole string in MD format and introduce %link%? For example for my link: [\(%priority%\) \[%key%\] %summary%](%link%) will be placed as is in MD mode and respectfully for OrgMode
@baflo @adyscorpius what you think?

[baflo]

@stantler I like your idea, too. Nevertheless, your link format seems to work for me 🤔

It would create literally this: [(Blocker) \[SCH-2105\] Test Summary](https://jira.lvm.de/jira/browse/SCH-2105)

[baflo]

@stantler @adyscorpius
I changed it to the proposition of formatExpertMode. This seems to be more stable and easier to use :)

[stantler]

Looks great and much better to understand. Thank you!