Fix file input delete styles

[raquelarrojo]

Checklist (Check off all the items before submitting)

• [x] Build process is done without errors. All tests pass in the /lib directory.
• [x] Self-reviewed the code before submitting.
• [x] Meets accessibility standards.
• [ ] Added/updated documentation to /website as needed.
• [ ] Added/updated tests as needed.

Description File input's delete icon was not centered. Added justify-content: center to the button.

Screenshots Before:

Now:

Closes #1994