fix: remove background under the dependency delete button

[ilandikov]

Description

The change is seen only on the dark theme.

Before

After (Note the background under the "x" is gone)

On the clear theme the is no change in color, only the shape slightly changed. After:

Motivation and Context

• have a prettier task modal =)

How has this been tested?

• manual test in demo valuet

Screenshots (if appropriate)

Types of changes

Changes visible to users:

• Bug fix (prefix: fix - non-breaking change which fixes an issue)

Checklist

• My code follows the code style of this project and passes yarn run lint.
• My change has adequate Unit Test coverage.

(I don't consider this a big enough change to update the modal screenshot)

Terms

• My contribution follows this project's contributing guide
• I agree to follow this project's Code of Conduct

[claremacrae]

I personally feel that having the visible difference around the x in dark mode made the behaviour clearer - that is, make it obvious that the x was not a part of the preceding text - but I don't mind enough to spend any time debating it...

Approving and merging.