[8.6] [Enterprise Search] Make add domain input full width (#148064) (#148072)

# Backport

This will backport the following commits from `main` to `8.6`:
- [[Enterprise Search] Make add domain input full width
(#148064)](https://github.com/elastic/kibana/pull/148064)

<!--- Backport version: 8.9.7 -->

### Questions ?
Please refer to the [Backport tool
documentation](https://github.com/sqren/backport)

<!--BACKPORT [{"author":{"name":"Sander
Philipse","email":"94373878+sphilipse@users.noreply.github.com"},"sourceCommit":{"committedDate":"2022-12-23T16:46:26Z","message":"[Enterprise
Search] Make add domain input full width (#148064)\n\nThis makes the add
domain input in the Elastic crawler full
width","sha":"ff228e6470955949cca74540f5e40682eeddaf9d","branchLabelMapping":{"^v8.7.0$":"main","^v(\\d+).(\\d+).\\d+$":"$1.$2"}},"sourcePullRequest":{"labels":["release_note:skip","Team:EnterpriseSearch","v8.6.0","v8.7.0"],"number":148064,"url":"https://github.com/elastic/kibana/pull/148064","mergeCommit":{"message":"[Enterprise
Search] Make add domain input full width (#148064)\n\nThis makes the add
domain input in the Elastic crawler full
width","sha":"ff228e6470955949cca74540f5e40682eeddaf9d"}},"sourceBranch":"main","suggestedTargetBranches":["8.6"],"targetPullRequestStates":[{"branch":"8.6","label":"v8.6.0","labelRegex":"^v(\\d+).(\\d+).\\d+$","isSourceBranch":false,"state":"NOT_CREATED"},{"branch":"main","label":"v8.7.0","labelRegex":"^v8.7.0$","isSourceBranch":true,"state":"MERGED","url":"https://github.com/elastic/kibana/pull/148064","number":148064,"mergeCommit":{"message":"[Enterprise
Search] Make add domain input full width (#148064)\n\nThis makes the add
domain input in the Elastic crawler full
width","sha":"ff228e6470955949cca74540f5e40682eeddaf9d"}}]}] BACKPORT-->

Co-authored-by: Sander Philipse <94373878+sphilipse@users.noreply.github.com>

x-pack/plugins/enterprise_search/public/applications/enterprise_search_content/components/search_index/crawler/domain_management/add_domain/add_domain_form.tsx

@@ -57,7 +57,10 @@ export const AddDomainForm: React.FC = () => {
         >
           <EuiFlexGroup>
             <EuiFlexItem grow>
-              <EuiFormControlLayout clear={{ onClick: () => setAddDomainFormInputValue('') }}>
+              <EuiFormControlLayout
+                clear={{ onClick: () => setAddDomainFormInputValue('') }}
+                fullWidth
+              >
                 <EuiFieldText
                   autoFocus
                   value={addDomainFormInputValue}