* cmd_runner module utils: fix case for as_fixed() format
* add changelog fragment
* simplified test_cmd_runner
* fix handling empty default for `as_map()`
* add changelog fragment
* MissingArgumentValue is reraised in run()
(cherry picked from commit e87ca10b61)
Co-authored-by: Alexei Znamensky <103110+russoz@users.noreply.github.com>