regenerate CI workflows for the single-use approval label

[mcocdawc]

Description

Purely trigger the downstream CI from the CI itself.
This means it's automatically gated behind the CI approval of the CI.

Get rid of the contributor declaration test.

Contributor Declaration

By opening this pull request, I affirm the following:

• All authors agree to the Contributor License Agreement.
• The code follows the project's coding standards.
• I have performed self-review and added comments where needed.
• I have added or updated tests to verify that my changes are effective and functional.
• I have run all existing tests and confirmed they pass.

🌦️ >> Documentation << 🌦️
https://sites.ecmwf.int/docs/dev-section/eckit/pull-requests/PR-338

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 67.58%. Comparing base (c8fd636) to head (d969653).

Additional details and impacted files

@@                   Coverage Diff                   @@
##           job-name-from-resolved     #338   +/-   ##
=======================================================
  Coverage                   67.58%   67.58%           
=======================================================
  Files                        1182     1182           
  Lines                       61862    61862           
  Branches                     4675     4675           
=======================================================
+ Hits                        41811    41812    +1     
+ Misses                      20051    20050    -1     

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