Build Tooling: Rebuild stylesheets when imported styles are modified

[jeyip]

Description

The local dev environment wasn't reloading style updates properly when modifying stylesheets that were separate (but imported) by another package.

Ex. Updates to styles in the interface package were not being propagated to the site editor stylesheet (which imports interface package styles, and should, theoretically, update as well)

How has this been tested?

1. Set up a local dev environment for Gutenberg
2. Set up the local WordPress instance with Docker (npx wp-env start)
3. Run npm run dev
4. Navigate to the site editor
5. Open up the block inserter
6. Note that the background color of the block inserter is white
7. Update styles in packages/interface/src/components/interface-skeleton/style.scss:98 and change the background-color to something notable, like purple
8. Refresh the page after waiting some period for the stylesheets to rebuild
9. Note that the background color of the block inserter is now purple
10. Open packages/interface/build-style/style.css:317 and packages/edit-site/build-style/style.css:317. These are the transpiled stylesheets that should reflect up to date styling changes. Confirm that the background color has been updated to purple in both of these files.

Types of changes

Bug fix for #26669

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: 0 B

Total Size: 1.21 MB

ℹ️ View Unchanged

Filename	Size	Change
build/a11y/index.js	1.14 kB	0 B
build/annotations/index.js	3.78 kB	0 B
build/api-fetch/index.js	3.45 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/index.js	133 kB	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	8.96 kB	0 B
build/block-library/editor.css	8.96 kB	0 B
build/block-library/index.js	147 kB	0 B
build/block-library/style-rtl.css	8.03 kB	0 B
build/block-library/style.css	8.03 kB	0 B
build/block-library/theme-rtl.css	792 B	0 B
build/block-library/theme.css	793 B	0 B
build/block-serialization-default-parser/index.js	1.88 kB	0 B
build/block-serialization-spec-parser/index.js	3.1 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	9.81 kB	0 B
build/core-data/index.js	12.5 kB	0 B
build/data-controls/index.js	772 B	0 B
build/data/index.js	8.8 kB	0 B
build/date/index.js	31.8 kB	0 B
build/deprecated/index.js	768 B	0 B
build/dom-ready/index.js	571 B	0 B
build/dom/index.js	4.46 kB	0 B
build/edit-navigation/index.js	11.2 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	6.41 kB	0 B
build/edit-post/style.css	6.39 kB	0 B
build/edit-site/index.js	22.6 kB	0 B
build/edit-site/style-rtl.css	3.91 kB	0 B
build/edit-site/style.css	3.91 kB	0 B
build/edit-widgets/index.js	26.3 kB	0 B
build/edit-widgets/style-rtl.css	3.12 kB	0 B
build/edit-widgets/style.css	3.12 kB	0 B
build/editor/editor-styles-rtl.css	480 B	0 B
build/editor/editor-styles.css	482 B	0 B
build/editor/index.js	42.8 kB	0 B
build/editor/style-rtl.css	3.85 kB	0 B
build/editor/style.css	3.85 kB	0 B
build/element/index.js	4.65 kB	0 B
build/escape-html/index.js	735 B	0 B
build/format-library/index.js	6.76 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	2.16 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	712 B	0 B
build/keyboard-shortcuts/index.js	2.52 kB	0 B
build/keycodes/index.js	1.94 kB	0 B
build/list-reusable-blocks/index.js	3.11 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	5.34 kB	0 B
build/notices/index.js	1.79 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	2.85 kB	0 B
build/reusable-blocks/index.js	3.06 kB	0 B
build/rich-text/index.js	13.2 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	4.06 kB	0 B
build/viewport/index.js	1.84 kB	0 B
build/warning/index.js	1.14 kB	0 B
build/wordcount/index.js	1.22 kB	0 B

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[Addison-Stavlo]

This is working well for me! Its actually updating the scss on save. 😄 🎉

[david-szabo97]

Tested following your testing steps. It's working perfectly! 👍 🥳 Code looks good to me!