[Widgets Editor] Remove default hover background in panel title

[kevin940726]

Description

Fix #25752.

Remove the default hover background in panel title.

How has this been tested?

1. Go to the Widgets screen
2. Try hover over some widget area's title
3. Observe that there's no background change in the title

Screenshots

Types of changes

Bug fix

Checklist:

• My code is tested.
• My code follows the WordPress code style.
• My code follows the accessibility standards.
• My code has proper inline documentation.
• I've included developer documentation if appropriate.
• I've updated all React Native files affected by any refactorings/renamings in this PR.

[github-actions]

Size Change: +39 B (0%)

Total Size: 1.18 MB

Filename	Size	Change
build/edit-widgets/style-rtl.css	3.02 kB	+19 B (0%)
build/edit-widgets/style.css	3.02 kB	+20 B (0%)

ℹ️ View Unchanged

Filename	Size	Change
build/a11y/index.js	1.14 kB	0 B
build/annotations/index.js	3.52 kB	0 B
build/api-fetch/index.js	3.35 kB	0 B
build/autop/index.js	2.72 kB	0 B
build/blob/index.js	668 B	0 B
build/block-directory/index.js	8.55 kB	0 B
build/block-directory/style-rtl.css	943 B	0 B
build/block-directory/style.css	942 B	0 B
build/block-editor/index.js	129 kB	0 B
build/block-editor/style-rtl.css	10.9 kB	0 B
build/block-editor/style.css	10.9 kB	0 B
build/block-library/editor-rtl.css	8.65 kB	0 B
build/block-library/editor.css	8.65 kB	0 B
build/block-library/index.js	135 kB	0 B
build/block-library/style-rtl.css	7.66 kB	0 B
build/block-library/style.css	7.65 kB	0 B
build/block-library/theme-rtl.css	741 B	0 B
build/block-library/theme.css	741 B	0 B
build/block-serialization-default-parser/index.js	1.78 kB	0 B
build/block-serialization-spec-parser/index.js	3.1 kB	0 B
build/blocks/index.js	47.5 kB	0 B
build/components/index.js	170 kB	0 B
build/components/style-rtl.css	15.4 kB	0 B
build/components/style.css	15.4 kB	0 B
build/compose/index.js	9.42 kB	0 B
build/core-data/index.js	12 kB	0 B
build/data-controls/index.js	685 B	0 B
build/data/index.js	8.6 kB	0 B
build/date/index.js	31.9 kB	0 B
build/deprecated/index.js	772 B	0 B
build/dom-ready/index.js	568 B	0 B
build/dom/index.js	4.42 kB	0 B
build/edit-navigation/index.js	10.7 kB	0 B
build/edit-navigation/style-rtl.css	868 B	0 B
build/edit-navigation/style.css	871 B	0 B
build/edit-post/index.js	306 kB	0 B
build/edit-post/style-rtl.css	6.29 kB	0 B
build/edit-post/style.css	6.27 kB	0 B
build/edit-site/index.js	20.8 kB	0 B
build/edit-site/style-rtl.css	3.71 kB	0 B
build/edit-site/style.css	3.72 kB	0 B
build/edit-widgets/index.js	21.4 kB	0 B
build/editor/editor-styles-rtl.css	492 B	0 B
build/editor/editor-styles.css	493 B	0 B
build/editor/index.js	45.5 kB	0 B
build/editor/style-rtl.css	3.85 kB	0 B
build/editor/style.css	3.84 kB	0 B
build/element/index.js	4.44 kB	0 B
build/escape-html/index.js	734 B	0 B
build/format-library/index.js	7.48 kB	0 B
build/format-library/style-rtl.css	547 B	0 B
build/format-library/style.css	548 B	0 B
build/hooks/index.js	1.74 kB	0 B
build/html-entities/index.js	621 B	0 B
build/i18n/index.js	3.54 kB	0 B
build/is-shallow-equal/index.js	710 B	0 B
build/keyboard-shortcuts/index.js	2.39 kB	0 B
build/keycodes/index.js	1.85 kB	0 B
build/list-reusable-blocks/index.js	3.02 kB	0 B
build/list-reusable-blocks/style-rtl.css	476 B	0 B
build/list-reusable-blocks/style.css	476 B	0 B
build/media-utils/index.js	5.12 kB	0 B
build/notices/index.js	1.69 kB	0 B
build/nux/index.js	3.27 kB	0 B
build/nux/style-rtl.css	671 B	0 B
build/nux/style.css	668 B	0 B
build/plugins/index.js	2.44 kB	0 B
build/primitives/index.js	1.34 kB	0 B
build/priority-queue/index.js	790 B	0 B
build/redux-routine/index.js	2.85 kB	0 B
build/rich-text/index.js	13 kB	0 B
build/server-side-render/index.js	2.6 kB	0 B
build/shortcode/index.js	1.7 kB	0 B
build/token-list/index.js	1.24 kB	0 B
build/url/index.js	4.06 kB	0 B
build/viewport/index.js	1.74 kB	0 B
build/warning/index.js	1.13 kB	0 B
build/wordcount/index.js	1.17 kB	0 B

_{compressed-size-action}

[draganescu]

Fixes the problem.