Fix incorrect size and position for radio focus indicator

[Jacalz]

Description:

This fixes an issue where the incorrect amount of padding was added to the focus indicator in radioItem.

Before:

After:

Checklist:

• Tests included.
• Lint and formatter run with no errors.
• Tests all pass.

[coveralls]

Coverage increased (+0.006%) to 61.451% when pulling d0f567e on Jacalz:fix/radio-focus-indicator into 7a3ae4d on fyne-io:release/v2.2.x.

[Bluebugs]

It would be nice to split commit next time with cosmetic change (like *0.5 -> /2 or reordering code) that are orthogonal to the fix to a different commit to make review a bit easier.

[Jacalz]

It would be nice to split commit next time with cosmetic change (like *0.5 -> /2 or reordering code) that are orthogonal to the fix to a different commit to make review a bit easier.

Sure thing. Sorry about that.