[Global Search Bar] Ensure the search controls are visible in low DPI screens

[tsullivan]

Summary

Closes #154415 by applying the fix suggested by Cee Chen.

Checklist

Delete any items that are not applicable to this PR.

• Any text added follows EUI's writing guidelines, uses sentence case text and includes i18n support
• Documentation was added for features that require explanation or tutorials
• Unit or functional tests were updated or added to match the most common scenarios
• Any UI touched in this PR is usable by keyboard only (learn more about keyboard accessibility)
• Any UI touched in this PR does not create any new axe failures (run axe in browser: FF, Chrome)
• If a plugin configuration key changed, check if it needs to be allowlisted in the cloud and added to the docker list
• This renders correctly on smaller devices using a responsive layout. (You can test this in your browser)
• This was checked for cross-browser compatibility

[elasticmachine]

Pinging @elastic/appex-sharedux (Team:SharedUX)

[kibana-ci]

💛 Build succeeded, but was flaky

• Buildkite Build
• Commit: c36977e

Failed CI Steps

• FTR Configs #29

Test Failures

• [job] [logs] FTR Configs #29 / Machine Learning jobs update groups "before all" hook for "returns expected list of groups after update"

Metrics [docs]

Page load bundle

Size of the bundles that are downloaded on every page load. Target size is below 100kb

id	before	after	diff
globalSearchBar	26.2KB	26.3KB	+102.0B

Unknown metric groups

ESLint disabled line counts

id	before	after	diff
enterpriseSearch	14	16	+2
securitySolution	408	412	+4
total			+6

Total ESLint disabled count

id	before	after	diff
enterpriseSearch	15	17	+2
securitySolution	487	491	+4
total			+6

To update your PR or re-run it, just comment with:
@elasticmachine merge upstream

cc @tsullivan