REF Extract case action links into a separate function to facilitate refactoring

[mattwire]

Overview

This is a simple refactor to extract the code that generates the case activity links.

They should be generated using CRM_Core_Action so they use standard CiviCRM markup and pass through hooks etc. but we need to disentangle the code first.

Before

Link generation in shared function

After

Link generation in it's own function, variables specific to generating links are moved to this function. There are a couple of extra things being conditionally set that should be moved out of this function (status_id and no_attachments) but that's for the next round.

Technical Details

Simple function extraction.

Comments

@colemanw As it's case related are you able to take a look? I know there's a lot of improvements that could be made here but I'd like to start with the simple extraction if that's ok and make improvements to the code in subsequent PRs.

[civibot]

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[eileenmcnaughton]

@mattwire style issues

[eileenmcnaughton]

Also I agree with extractions NOT being mixed with other changes - that makes them hard to review

[mattwire]

This branch shows where this might be heading... master...mattwire:case_links_refactor_part2

[eileenmcnaughton]

I worked through this refactor locally and was able to get the same result so I'm going to merge.

But if we are gonna be doing a tidy up in this area I think the next iteration should include tests