Accessibility: Linter issues with the border, width etc.

[magdalenajadach]

Related to https://github.com/RaspberryPiFoundation/editor-ui/pull/770/files

[create-issue-branch]

Branch a11y/786-Accessibility_Linter_issues_with_the_border_width_etc created!

[magdalenajadach]

After the recent PR merge only 189 issues left

[magdalenajadach]

[magdalenajadach]