Outline button: inherits background-image if gradient is applied

[mikachan]

Description

The 'outline' style of the button block incorrectly inherits the background-image property if a button.color.gradient is used in theme.json. I believe this should be set to none, in the same way as the 'outline' style sets the background-color to transparent, in order for this button style to be an outline button.

See the Pilgrimage TT3 style variation for an example of this:

Step-by-step reproduction instructions

1. Enable TT3 and pick the Pilgrimage style variation
2. Insert a button block with the 'outline' style
3. See that the background property is inherited from the default button settings:

Screenshots, screen recording, code snippet

No response

Environment info

• WP 6.1 RC2, GB 14.4.0

Please confirm that you have searched existing issues in the repo.

Yes

Please confirm that you have tested with all plugins deactivated except Gutenberg.

Yes