Fix Review app Sass compile after error

[colinrotherham]

This PR fixes Gulp "Did you forget to signal async completion?" when Sass compilation errors occur in:

• The review app stops compiling Sass after encountering an error #4237

The issue

Spot my missing await in 8f74d02 🤦‍♂️

Error logging

I've made sure all "watch + reload" tasks use Gulp's new PluginError() for consistent output, as currently:

1. Sass tasks via scripts.compile() throw new PluginError()
2. Rollup tasks via styles.compile() throw new PluginError()
3. npm tasks via npm.script() log console.error(error.message) without error

But Gulp is now aware of npm task errors too, without interrupting watch tasks:

[github-actions]

📋 Stats

File sizes

File	Size
dist/govuk-frontend-4.6.0.min.css	118.07 KiB
dist/govuk-frontend-4.6.0.min.js	47.1 KiB
dist/govuk-frontend-ie8-4.6.0.min.css	79.27 KiB
packages/govuk-frontend/dist/govuk/all.bundle.js	76.42 KiB
packages/govuk-frontend/dist/govuk/all.bundle.mjs	71.79 KiB
packages/govuk-frontend/dist/govuk/all.mjs	3.84 KiB
packages/govuk-frontend/dist/govuk/govuk-frontend-component.mjs	359 B
packages/govuk-frontend/dist/govuk/govuk-frontend.min.js	37.16 KiB
packages/govuk-frontend/dist/govuk/i18n.mjs	5.83 KiB

Modules

File	Size
all.mjs	67.89 KiB
components/accordion/accordion.mjs	21.9 KiB
components/button/button.mjs	4.71 KiB
components/character-count/character-count.mjs	21.64 KiB
components/checkboxes/checkboxes.mjs	5.69 KiB
components/error-summary/error-summary.mjs	6.01 KiB
components/exit-this-page/exit-this-page.mjs	16.6 KiB
components/header/header.mjs	3.34 KiB
components/notification-banner/notification-banner.mjs	4.54 KiB
components/radios/radios.mjs	4.68 KiB
components/skip-link/skip-link.mjs	3.73 KiB
components/tabs/tabs.mjs	9.07 KiB

View stats and visualisations on the review app

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Action run for 089b280

[romaricpascal]

Whoops! So easy to miss these await. Thanks for the little tidy-ups around as well :D

[colinrotherham]

Thanks @romaricpascal

Just need to confirm those error codes etc in Windows before merging

[36degrees]

🙌🏻

[colinrotherham]

To avoid unnecessary error logging on Windows I've silenced { code: 3221225786 } as shown:

• The terminal process terminated with exit code: 3221225786 microsoft/vscode#107501
• Use a wrapper to properly test CTRL-C event on Windows open-cli-tools/concurrently#359

Don't want to make Ctrl + C too noisy on Windows if we can avoid it there too