ci: run e2e tests on macOS and Windows

[rishi-jat]

Summay

• Expand e2e CI to matrix: ubuntu, macOS, Windows
• Use cargo test --test "*" for cross‑platform runs
• Gate Docker/testcontainers tests to Linux; add no-op stubs on other OSes
• Windows: enable git long paths and set CMAKE_POLICY_VERSION_MINIMUM=3.5

Fixes #1189

[rishi-jat]

@flavio please review when you get a chance.Thanks!

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 87.50%. Comparing base (b293ac3) to head (6ff3c32).
⚠️ Report is 6 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1351   +/-   ##
=======================================
  Coverage   87.50%   87.50%           
=======================================
  Files          34       34           
  Lines        4947     4947           
=======================================
  Hits         4329     4329           
  Misses        618      618           

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[flavio]

the changes look good to me, I also like the approach you used to handle the test containers dependency on windows and mac.

However, the e2e test are currently failing on these platforms (or are not run). Can you look into that?

[viccuad]

The current change seems to not be enough, can you have a look please?
https://github.com/kubewarden/kwctl/actions/runs/17533714097/job/49823266040?pr=1351#step:6:1409

[rishi-jat]

sorry, for late will fix the ci errors soon.