Make user input heading container expand to full width.

[jimmymadon]

Summary

Addresses issue:

• Issues with Key metrics section in Admin settings page responsiveness on 601px to 653px viewports #7564

Relevant technical choices

PR Author Checklist

• My code is tested and passes existing unit tests.
• My code has an appropriate set of unit tests which all pass.
• My code is backward-compatible with WordPress 5.2 and PHP 7.4.
• My code follows the WordPress coding standards.
• My code has proper inline documentation.
• I have added a QA Brief on the issue linked above.
• I have signed the Contributor License Agreement (see https://cla.developers.google.com/).

---

Do not alter or remove anything below. The following sections will be managed by moderators only.

Code Reviewer Checklist

• Run the code.
• Ensure the acceptance criteria are satisfied.
• Reassess the implementation with the IB.
• Ensure no unrelated changes are included.
• Ensure CI checks pass.
• Check Storybook where applicable.
• Ensure there is a QA Brief.

Merge Reviewer Checklist

• Ensure the PR has the correct target branch.
• Double-check that the PR is okay to be merged.
• Ensure the corresponding issue has a ZenHub release assigned.
• Add a changelog message to the issue.

[github-actions]

Build files for 0afa3c6 have been deleted.

[github-actions]

Size Change: -16 B (0%)

Total Size: 1.51 MB

Filename	Size	Change
./dist/assets/js/googlesitekit-settings-********************.js	61.4 kB	-10 B (-0.02%)
./dist/assets/js/googlesitekit-user-input-********************.js	48.1 kB	-6 B (-0.01%)

ℹ️ View Unchanged

Filename	Size
./dist/assets/css/googlesitekit-admin-css-********************.min.css	54.3 kB
./dist/assets/css/googlesitekit-adminbar-css-********************.min.css	11.2 kB
./dist/assets/css/googlesitekit-authorize-application-css-********************.min.css	734 B
./dist/assets/css/googlesitekit-wp-dashboard-css-********************.min.css	7.48 kB
./dist/assets/js/29-********************.js	2.8 kB
./dist/assets/js/30-********************.js	2.28 kB
./dist/assets/js/31-********************.js	3.72 kB
./dist/assets/js/32-********************.js	929 B
./dist/assets/js/33-********************.js	889 B
./dist/assets/js/34-********************.js	3.12 kB
./dist/assets/js/analytics-advanced-tracking-********************.js	778 B
./dist/assets/js/contact-form-7-********************.js	646 B
./dist/assets/js/googlesitekit-activation-********************.js	23.9 kB
./dist/assets/js/googlesitekit-ad-blocking-recovery-********************.js	58.9 kB
./dist/assets/js/googlesitekit-adminbar-********************.js	34.6 kB
./dist/assets/js/googlesitekit-api-********************.js	10.2 kB
./dist/assets/js/googlesitekit-components-gm2-********************.js	5.88 kB
./dist/assets/js/googlesitekit-components-gm3-********************.js	10 kB
./dist/assets/js/googlesitekit-data-********************.js	2.18 kB
./dist/assets/js/googlesitekit-datastore-forms-********************.js	9.14 kB
./dist/assets/js/googlesitekit-datastore-location-********************.js	2.09 kB
./dist/assets/js/googlesitekit-datastore-site-********************.js	19.9 kB
./dist/assets/js/googlesitekit-datastore-ui-********************.js	10.1 kB
./dist/assets/js/googlesitekit-datastore-user-********************.js	25.2 kB
./dist/assets/js/googlesitekit-entity-dashboard-********************.js	73.7 kB
./dist/assets/js/googlesitekit-i18n-********************.js	3.92 kB
./dist/assets/js/googlesitekit-main-dashboard-********************.js	117 kB
./dist/assets/js/googlesitekit-modules-ads-********************.js	27 kB
./dist/assets/js/googlesitekit-modules-adsense-********************.js	112 kB
./dist/assets/js/googlesitekit-modules-analytics-4-********************.js	129 kB
./dist/assets/js/googlesitekit-modules-********************.js	22.1 kB
./dist/assets/js/googlesitekit-modules-pagespeed-insights-********************.js	22.5 kB
./dist/assets/js/googlesitekit-modules-search-console-********************.js	58.2 kB
./dist/assets/js/googlesitekit-modules-tagmanager-********************.js	30.4 kB
./dist/assets/js/googlesitekit-polyfills-********************.js	380 B
./dist/assets/js/googlesitekit-splash-********************.js	72.9 kB
./dist/assets/js/googlesitekit-vendor-********************.js	317 kB
./dist/assets/js/googlesitekit-widgets-********************.js	49.8 kB
./dist/assets/js/googlesitekit-wp-dashboard-********************.js	60 kB
./dist/assets/js/mailchimp-********************.js	632 B
./dist/assets/js/optin-monster-********************.js	669 B
./dist/assets/js/popup-maker-********************.js	634 B
./dist/assets/js/runtime-********************.js	1.3 kB
./dist/assets/js/woocommerce-********************.js	655 B
./dist/assets/js/wpforms-********************.js	634 B

_{compressed-size-action}

[kuasha420]

Thanks @jimmymadon. LGTM 🎉