Make console wider during tests, tweak logger

[lebrice]

• Makes the console wider during tests.
  • This will become useful for future tests like the ones for mila code and such, which produce quite long commands.
• Make the Rich logging handler use the Rich console instead of creating a new one.
  • This fixes a bad interaction between logging messages and the progress bars (e.g. in mila sync vscode-extensions or mila code --cluster=<drac>)