implement fetchWithAbort and use it for partial page load, mappings & alphabetical index

[osma]

Reasons for creating this PR

Trying to address the AJAX race conditions related to partial page load (#1561).

This PR defines a new JS function fetchWithAbort that wraps the fetch method but also keeps track of pending fetches (per category - there can be different categories) and aborts them early when it's called again.

Link to relevant issue(s), if any

• Closes Race conditions in Skosmos 3 AJAX requests #1561

Description of the changes in this PR

• define function fetchWithAbort
• use fetchWithAbort when performing partial page load and also when loading mappings for the concept page
• use fetchWithAbort when loading entries for the alphabetical index

Known problems or uncertainties in this PR

• The PR doesn't interact with the search field autocomplete widget, which is still WIP in PR Implement autocomplete for search #1589. I think the fetchWithAbort function would be useful there as well.
• Should there be Cypress tests? How would they work?

Checklist

• phpUnit tests pass locally with my changes
• I have added tests that show that the new code works, or tests are not relevant for this PR (e.g. only HTML/CSS changes)
• The PR doesn't reduce accessibility of the front-end code (e.g. tab focus, scaling to different resolutions, use of .sr-only class, color contrast)
• The PR doesn't introduce unintended code changes (e.g. empty lines or useless reindentation)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 70.58%. Comparing base (f22c504) to head (fcf5be7).
Report is 5 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##               main    #1609   +/-   ##
=========================================
  Coverage     70.58%   70.58%           
  Complexity     1647     1647           
=========================================
  Files            32       32           
  Lines          4321     4321           
=========================================
  Hits           3050     3050           
  Misses         1271     1271           

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[UnniKohonen]

The code looks good to me and it seems to work correctly.

Cypress tests for partial page load on vocabulary home page fail sometimes because timeout isn't high enough. Not sure if the problem should be addressed in here, though, as it doesn't seem to originate from this PR.

[osma]

You are right @UnniKohonen . I will increase the timeouts. I think it makes sense to do this on this PR branch rather than makkng a separate PR because the timeout problem is closely related even though it's probably not caused by new changes in this PR.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarCloud