Fix autocomplete on only 1 letter typed in request editor

[sakurai-youhei]

Summary

This PR fixes autocomplete on only 1 letter typed in request editor.

Closes #164542

Checklist

• Unit or functional tests were updated or added to match the most common scenarios

For maintainers

• This was checked for breaking API changes and was labeled appropriately

Release note

Fixes autocomplete on only 1 letter typed in Console's request editor

[kibana-ci]

💛 Build succeeded, but was flaky

• Buildkite Build
• Commit: 1acb623

Failed CI Steps

• FTR Configs #10

Test Failures

• [job] [logs] FTR Configs #10 / lens app - group 5 lens visualize geo field tests should visualize geo fields in maps

Metrics [docs]

Async chunks

Total size of all lazy-loaded chunks that will be downloaded as the user navigates the app

id	before	after	diff
console	418.3KB	418.2KB	-105.0B

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

[sakurai-youhei]

Note that tests were not disabled at the time of build 153141, which proves the proposed fix by them. Refer HERE.

I recommend merging #164706 first, which lets you check whether or not this fix breaks behaviors described in #136056.

[yuliacech]

Thanks a lot for fixing this, @sakurai-youhei!
Tested locally and was not able to reproduce the issue.