gha: fix lychee

[bjlittle]

🚀 Pull Request

Description

Playing forward some quality-of-life improvements and fixes to ci-linkcheck.yml, namely:

1. Improve readabilty for args and labels by using multi-line input
2. Group and rationalise multiple job runs with concurrency controls
3. Adopt artipacked pattern remediation as zizmor recommended best practice regarding actions/checkout persisted credentials
4. Fix incorrect if: syntax - GHAs use expressions inside ${{ ... }} for evaluation, otherwise the condition is treated as text, which can result in incorrect behaviour
   • Adopted fromJSON for readability. The flip would be to adopt ... != '0' instead.
5. Use fromJSON to coerce exit_code for integer comparison

As an aside, I'd recommend that iris should adopt zizmor compliance for static analysis of its GHAs 💯

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• benchmark_this Request that this pull request be benchmarked to check if it introduces performance shifts

[scitools-ci]

• Please see: SciTools/.github#230

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.39%. Comparing base (9bd0970) to head (5886042).
⚠️ Report is 69 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #6808   +/-   ##
=======================================
  Coverage   90.39%   90.39%           
=======================================
  Files          91       91           
  Lines       24761    24761           
  Branches     4639     4639           
=======================================
  Hits        22382    22382           
  Misses       1608     1608           
  Partials      771      771           

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[ukmo-ccbunney]

This all looks very sensible to me. Good catch on the plain text if conditions. 👍🏼
LGTM.

[ukmo-ccbunney]

Just the template to action here, then we're good to merge. 👍🏼

[bjlittle]

Just the template to action here, then we're good to merge. 👍🏼

@ukmo-ccbunney see SciTools/.github#231

[bjlittle]

@ukmo-ccbunney For extra credit ... also raised issue #6809 😉

[ukmo-ccbunney]

Nice! All good to go. 🚀

Template update addresses in referenced PR