Fix large tests in debug mode

* The profile was taken into account, but the reflected INFO: Logging level set
  to… was erroneous (always the default one)
* Set the right profile key for debug mode
* Skip then in parsing this special message as it can be set to WARNING or
  set to ERROR, and it shouldn't be taken into account in the warning/error
  expected check (apart in the test_basics_cli).
Remove default_file logging level attribute

* This wasn't use and people can either use the environment variable or
  premade parameters.
Minor cleanup and some debug info.
Add a copy_icon tools functionality

* That helper will be used when we need to install an icon in the user
  directory.
* Add tests to ensure we can update the icon as well.
Cleanup create_launcher

* Make it reflecting copy_icon to not duplicate launcher path logic
Add a test to ensure we can update the launcher

* Ensure we can update the launcher content.
* Some misleading test comment update.
Rename launcher_path to desktop_filename
For medium tests, generically replace HOME

* As some content like icon or launcher path are based on the user HOME
  directory, set the one corresponding to the docker user container for
  medium tests