Set commit author name and email

[sclause2412]

Is your feature request related to a problem? Please describe.
If I checkout a repository and want to commit something it fails with "Author identity unknown". This is because I have NOT set an author globally. I do not want to do it globally because I sometimes want to commit with my private account and sometimes with my work account. If I set it globally I will forget to change and then I have issues solving it out.

Describe the solution you'd like
If there is no author given then lazygit could inform and ask for an author. Could be same dialog as for "Amend commit attribute..." command.
Another possibility is to just have a keybinding for setting an author. Example: Use similar keybinding as for "Amend commit attribute..." (e.g. Ctrl+a) but if used in Files view then it is called "Set author...".

Describe alternatives you've considered
Custom Commands can be used - but hey, it's a feature request, not a bug :-)

Additional context
Custom command version:

customCommands:
  - key: '<c-a>'
    context: 'files'
    description: 'Set author'
    prompts:
      - type: 'input'
        title: 'What is the new author name?'
        key: 'Author'
        initialValue: ''
        suggestions:
          preset: 'authors'
    command: 'git config user.name "$(echo "{{.Form.Author}}" | sed -E "s/^(.*) <.*>$/\1/")" && git config user.email "$(echo "{{.Form.Author}}" | se>