ci: add meson setup -D {distconf,module}dir=relative/ checks

[evelikov]

Based on the autotools build, meson does not support relative directories for distconfig and moduledir. We fixed that recently, but never added a check so we don't regress.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

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🚨 Try these New Features:

• Flaky Tests Detection - Detect and resolve failed and flaky tests

[lucasdemarchi]

Applied, thanks