Prevent the cover block from overriding the children blocks colors

[youknowriad]

I'm not really sure what was the purpose of this style. cc @jorgefilipecosta

Testing instructions

• Insert the "abc" pattern and notice that the text color is dark blue.

[github-actions]

Size Change: -23 B (0%)

Total Size: 857 kB

Filename	Size	Change
build/block-library/editor-rtl.css	7.21 kB	-11 B (0%)
build/block-library/editor.css	7.21 kB	-12 B (0%)

ℹ️ View Unchanged

Filename	Size	Change
build/a11y/index.js	998 B	0 B
build/annotations/index.js	3.45 kB	0 B
build/api-fetch/index.js	3.39 kB	0 B
build/autop/index.js	2.58 kB	0 B
build/blob/index.js	620 B	0 B
build/block-directory/index.js	6.02 kB	0 B
build/block-directory/style-rtl.css	760 B	0 B
build/block-directory/style.css	760 B	0 B
build/block-editor/index.js	102 kB	0 B
build/block-editor/style-rtl.css	11 kB	0 B
build/block-editor/style.css	11 kB	0 B
build/block-library/index.js	110 kB	0 B
build/block-library/style-rtl.css	7.49 kB	0 B
build/block-library/style.css	7.5 kB	0 B
build/block-library/theme-rtl.css	669 B	0 B
build/block-library/theme.css	671 B	0 B
build/block-serialization-default-parser/index.js	1.65 kB	0 B
build/block-serialization-spec-parser/index.js	3.1 kB	0 B
build/blocks/index.js	57.5 kB	0 B
build/components/index.js	190 kB	0 B
build/components/style-rtl.css	15.8 kB	0 B
build/components/style.css	15.7 kB	0 B
build/compose/index.js	6.21 kB	0 B
build/core-data/index.js	10.6 kB	0 B
build/data-controls/index.js	1.04 kB	0 B
build/data/index.js	8.26 kB	0 B
build/date/index.js	5.37 kB	0 B
build/deprecated/index.js	772 B	0 B
build/dom-ready/index.js	568 B	0 B
build/dom/index.js	3.06 kB	0 B
build/edit-post/index.js	91 kB	0 B
build/edit-post/style-rtl.css	8.43 kB	0 B
build/edit-post/style.css	8.43 kB	0 B
build/edit-site/index.js	6.64 kB	0 B
build/edit-site/style-rtl.css	2.98 kB	0 B
build/edit-site/style.css	2.98 kB	0 B
build/edit-widgets/index.js	4.43 kB	0 B
build/edit-widgets/style-rtl.css	2.57 kB	0 B
build/edit-widgets/style.css	2.57 kB	0 B
build/editor/editor-styles-rtl.css	423 B	0 B
build/editor/editor-styles.css	426 B	0 B
build/editor/index.js	42.8 kB	0 B
build/editor/style-rtl.css	3.38 kB	0 B
build/editor/style.css	3.38 kB	0 B
build/element/index.js	4.44 kB	0 B
build/escape-html/index.js	733 B	0 B
build/format-library/index.js	6.95 kB	0 B
build/format-library/style-rtl.css	502 B	0 B
build/format-library/style.css	502 B	0 B
build/hooks/index.js	1.93 kB	0 B
build/html-entities/index.js	622 B	0 B
build/i18n/index.js	3.57 kB	0 B
build/is-shallow-equal/index.js	710 B	0 B
build/keyboard-shortcuts/index.js	2.3 kB	0 B
build/keycodes/index.js	1.7 kB	0 B
build/list-reusable-blocks/index.js	2.99 kB	0 B
build/list-reusable-blocks/style-rtl.css	226 B	0 B
build/list-reusable-blocks/style.css	226 B	0 B
build/media-utils/index.js	4.84 kB	0 B
build/notices/index.js	1.57 kB	0 B
build/nux/index.js	3.01 kB	0 B
build/nux/style-rtl.css	616 B	0 B
build/nux/style.css	613 B	0 B
build/plugins/index.js	2.54 kB	0 B
build/primitives/index.js	1.5 kB	0 B
build/priority-queue/index.js	781 B	0 B
build/redux-routine/index.js	2.84 kB	0 B
build/rich-text/index.js	14.5 kB	0 B
build/server-side-render/index.js	2.55 kB	0 B
build/shortcode/index.js	1.7 kB	0 B
build/token-list/index.js	1.28 kB	0 B
build/url/index.js	4.01 kB	0 B
build/viewport/index.js	1.61 kB	0 B
build/warning/index.js	1.14 kB	0 B
build/wordcount/index.js	1.18 kB	0 B

_{compressed-size-action}

[mtias]

Probably because white as a default would work on more images by default? But we should do it through the paragraph attributes if that's the case, not through arbitrary CSS.