Consolidate native and managed test reporting

[papeh]

• Ensure that native tests are built by build.ps1 when requested
• Run both native and managed tests in test.ps1 by default
• Include stderr test logs in artifacts (stdout logs are already included)

Why Invoke-CppTest.ps1 builds native tests but build.ps1 did not remains a mystery to me.

This change  😁

[github-actions]

NUnit Tests

    1 files  ±0      1 suites  ±0   6m 24s ⏱️ +14s
4 103 tests ±0  4 032 ✅ ±0  71 💤 ±0  0 ❌ ±0 
4 112 runs  ±0  4 041 ✅ ±0  71 💤 ±0  0 ❌ ±0 

Results for commit e06913a. ± Comparison against base commit 1eacfff.

♻️ This comment has been updated with latest results.