Drop examples from coverage matrix (uploads nothing)

[JavierMonton]

The examples module has no main sources, so its two coverage jobs find no coverage files and upload nothing (the Codecov step errors out but exits 0, hiding it). They only add noise and extra tokenless uploads. Examples tests keep running in the Build and Test job. Follow-up still needed: configure the CODECOV_TOKEN repo secret, otherwise the 14 parallel tokenless uploads keep hitting Codecov rate limits (429) and random main runs will show phantom coverage drops.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.80%. Comparing base (9eb9c34) to head (aaff751).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #663   +/-   ##
=======================================
  Coverage   99.80%   99.80%           
=======================================
  Files          32       32           
  Lines         508      508           
  Branches       61       54    -7     
=======================================
  Hits          507      507           
  Misses          1        1           

Flag	Coverage Δ
unittests	99.01% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.