Multi selection: move hook to WritingFlow with other multi selection logic

[ellatrix]

Description

This is a small change. Currently, all logic for multi selecting blocks is in WritingFlow, except for the useMultiSelection hook, which is now added to the root container. This doesn't make sense.

In the future, BlocksList should ideally return a list of blocks without a wrapper element.

How has this been tested?

Screenshots

Types of changes

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: -57 B (0%)

Total Size: 1.19 MB

Filename	Size	Change
build/block-editor/index.js	128 kB	-57 B (0%)

ℹ️ View Unchanged

Filename	Size	Change
build/a11y/index.js	1.14 kB	0 B
build/annotations/index.js	3.8 kB	0 B
build/api-fetch/index.js	3.42 kB	0 B
build/autop/index.js	2.84 kB	0 B
build/blob/index.js	665 B	0 B
build/block-directory/index.js	8.72 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/style-rtl.css	11.2 kB	0 B
build/block-editor/style.css	11.2 kB	0 B
build/block-library/editor-rtl.css	8.88 kB	0 B
build/block-library/editor.css	8.88 kB	0 B
build/block-library/index.js	149 kB	0 B
build/block-library/style-rtl.css	8.34 kB	0 B
build/block-library/style.css	8.34 kB	0 B
build/block-library/theme-rtl.css	789 B	0 B
build/block-library/theme.css	790 B	0 B
build/block-serialization-default-parser/index.js	1.88 kB	0 B
build/block-serialization-spec-parser/index.js	3.06 kB	0 B
build/blocks/index.js	48.1 kB	0 B
build/components/index.js	172 kB	0 B
build/components/style-rtl.css	15.3 kB	0 B
build/components/style.css	15.3 kB	0 B
build/compose/index.js	9.95 kB	0 B
build/core-data/index.js	15.2 kB	0 B
build/data-controls/index.js	827 B	0 B
build/data/index.js	8.98 kB	0 B
build/date/index.js	11.2 kB	0 B
build/deprecated/index.js	768 B	0 B
build/dom-ready/index.js	571 B	0 B
build/dom/index.js	4.95 kB	0 B
build/edit-navigation/index.js	11.1 kB	0 B
build/edit-navigation/style-rtl.css	881 B	0 B
build/edit-navigation/style.css	885 B	0 B
build/edit-post/index.js	306 kB	0 B
build/edit-post/style-rtl.css	6.49 kB	0 B
build/edit-post/style.css	6.47 kB	0 B
build/edit-site/index.js	24.1 kB	0 B
build/edit-site/style-rtl.css	4.06 kB	0 B
build/edit-site/style.css	4.06 kB	0 B
build/edit-widgets/index.js	26.3 kB	0 B
build/edit-widgets/style-rtl.css	3.13 kB	0 B
build/edit-widgets/style.css	3.13 kB	0 B
build/editor/editor-styles-rtl.css	476 B	0 B
build/editor/editor-styles.css	478 B	0 B
build/editor/index.js	43.6 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	4.63 kB	0 B
build/escape-html/index.js	735 B	0 B
build/format-library/index.js	6.86 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	2.27 kB	0 B
build/html-entities/index.js	623 B	0 B
build/i18n/index.js	3.57 kB	0 B
build/is-shallow-equal/index.js	698 B	0 B
build/keyboard-shortcuts/index.js	2.54 kB	0 B
build/keycodes/index.js	1.93 kB	0 B
build/list-reusable-blocks/index.js	3.1 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	5.31 kB	0 B
build/notices/index.js	1.82 kB	0 B
build/nux/index.js	3.42 kB	0 B
build/nux/style-rtl.css	671 B	0 B
build/nux/style.css	668 B	0 B
build/plugins/index.js	2.56 kB	0 B
build/primitives/index.js	1.43 kB	0 B
build/priority-queue/index.js	791 B	0 B
build/redux-routine/index.js	2.84 kB	0 B
build/reusable-blocks/index.js	2.92 kB	0 B
build/rich-text/index.js	13.4 kB	0 B
build/server-side-render/index.js	2.77 kB	0 B
build/shortcode/index.js	1.69 kB	0 B
build/token-list/index.js	1.27 kB	0 B
build/url/index.js	2.84 kB	0 B
build/viewport/index.js	1.86 kB	0 B
build/warning/index.js	1.14 kB	0 B
build/wordcount/index.js	1.22 kB	0 B

_{compressed-size-action}