[MNT] Use MacOS for `examples/` workflow

[MatthewMiddlehurst]

Describe the issue

MacOS is generally faster for our CI, we should try running our examples workflow using it and see if there is a speed up.

Suggest a potential alternative/fix

Swap over to MacOS runners in the example CI. Evaluate whether this is faster than the current Linux runner.

Additional context

See #2390, these are the three files that will have to change (at least)

[shinymack]

@aeon-actions-bot assign @shinymack