[FIX] webui-templates: update time-elements library

[Corentvn]

The @github/time-element library is now deprecated. Its authors recommend using @github/relative-time-element instead.

This commit was motivated by the fact that Runboat uses the <time-ago> and time-elements@latest library, which currently points to version 4.0.0.
In this release, the <time-ago> component was removed in favor of <relative-time>.

Alternatively, pin the time-elements@3.6.0 instead of latest.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 64.59%. Comparing base (8813f67) to head (2aff751).
⚠️ Report is 57 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #151      +/-   ##
==========================================
- Coverage   64.97%   64.59%   -0.39%     
==========================================
  Files          19       19              
  Lines        1245     1257      +12     
==========================================
+ Hits          809      812       +3     
- Misses        436      445       +9     

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[Corentvn]

Hello @sbidoul,

I don't really get where I loose code coverage with this simple commit.
(Note: I'm not used to Codecov, but it seems it's not comparing the HEAD of this branch with HEAD of main but an older commit.)

Should we pin time-elements@3.6.0 instead of relative-time-element@latest ?

[sbidoul]

Let's go with this. Thanks!