Description

Tests using utf-8 characters fails in murdock native but work my developer machine.

• tests/lua_loader: run the test in CI tests/lua_loader: run the test in CI #11686
• tests/pkg_u8g2: run the test in CI tests/pkg_u8g2: run the test in CI #11687
• tests/pthread_rwlock: run the test in CI tests/pthread_rwlock: run the test in CI #11688

For the boards tests, it looks like they work correctly on the nodes but the report is not described as an utf-8 document so show invalid output in the reports by default.

Related to #9095 (comment)

Steps to reproduce the issue

Enable the given tests in CI and check the output.

Expected results

• Tests work in native correctly.
• Tests report show the utf-8 characters by default on boards.

Actual results

• Tests using utf-8 fail with UnicodeEncodeError: 'ascii' codec can't encode characters in position for native
• Encoding for file tests results is utf-8.

Versions

This is murdock specific so not RIOT.