refactor(tests): extract utils from NoteTypeTest

[david-allison]

I split this out the 'final' refactor for:

• Split libanki & tests into a separate module #18015

Checklist

• You have a descriptive commit message with a short title (first line, max 50 chars).
• You have commented your code, particularly in hard-to-understand areas
• You have performed a self-review of your own code
• UI changes: include screenshots of all affected screens (in particular showing any new or changed strings)
• UI Changes: You have tested your change using the Google Accessibility Scanner

[mikehardy]

test-only I see no reason to delay, would love to finish the refactor before any branch