[Discover] Fix issue with actions column header size (elastic#235227)

## Summary

This PR fixes the bug with showing "Actions" header column name even if
there was no space and info icon would fit better.
It uses the EuiResizeObserver to get the dimentions of the action column
and decide if we should show icon or full text.
Resolves: elastic#234647

### Checklist

Check the PR satisfies following conditions. 

Reviewers should verify this PR satisfies this list as well.

- [ ] Any text added follows [EUI's writing
guidelines](https://elastic.github.io/eui/#/guidelines/writing), uses
sentence case text and includes [i18n
support](https://github.com/elastic/kibana/blob/main/src/platform/packages/shared/kbn-i18n/README.md)
- [ ]
[Documentation](https://www.elastic.co/guide/en/kibana/master/development-documentation.html)
was added for features that require explanation or tutorials
- [ ] [Unit or functional
tests](https://www.elastic.co/guide/en/kibana/master/development-tests.html)
were updated or added to match the most common scenarios
- [ ] If a plugin configuration key changed, check if it needs to be
allowlisted in the cloud and added to the [docker
list](https://github.com/elastic/kibana/blob/main/src/dev/build/tasks/os_packages/docker_generator/resources/base/bin/kibana-docker)
- [ ] This was checked for breaking HTTP API changes, and any breaking
changes have been approved by the breaking-change committee. The
`release_note:breaking` label should be applied in these situations.
- [ ] [Flaky Test
Runner](https://ci-stats.kibana.dev/trigger_flaky_test_runner/1) was
used on any tests changed
- [ ] The PR description includes the appropriate Release Notes section,
and the correct `release_note:*` label is applied per the
[guidelines](https://www.elastic.co/guide/en/kibana/master/contributing.html#kibana-release-notes-process)
- [x] Review the [backport
guidelines](https://docs.google.com/document/d/1VyN5k91e5OVumlc0Gb9RPa3h1ewuPE705nRtioPiTvY/edit?usp=sharing)
and apply applicable `backport:*` labels.

Author: MiloszRadzynski

src/platform/packages/shared/kbn-unified-data-table/src/components/custom_control_columns/actions_column/actions_header.tsx

@@ -7,21 +7,28 @@
  * License v3.0 only", or the "Server Side Public License, v 1".
  */
 
-import React, { useLayoutEffect, useRef, useState } from 'react';
-import { EuiIconTip, EuiScreenReaderOnly } from '@elastic/eui';
+import React, { useCallback, useState } from 'react';
+import {
+  type EuiResizeObserverProps,
+  EuiIconTip,
+  EuiResizeObserver,
+  EuiScreenReaderOnly,
+} from '@elastic/eui';
 import { css } from '@emotion/react';
 import { i18n } from '@kbn/i18n';
 import ColumnHeaderTruncateContainer from '../../column_header_truncate_container';
 
 export const ActionsHeader = ({ maxWidth }: { maxWidth: number }) => {
-  const textRef = useRef<HTMLSpanElement>(null);
   const [showText, setShowText] = useState(false);
 
-  useLayoutEffect(() => {
-    if (!textRef.current) return;
-    const textWidth = textRef.current.getBoundingClientRect().width;
-    setShowText(textWidth < maxWidth);
-  }, [textRef, maxWidth, setShowText]);
+  const measure: EuiResizeObserverProps['onResize'] = useCallback(
+    (dimensions) => {
+      if (!dimensions) return;
+
+      setShowText(dimensions.width < maxWidth);
+    },
+    [maxWidth]
+  );
 
   const actionsText = i18n.translate('unifiedDataTable.controlColumnsActionHeader', {
     defaultMessage: 'Actions',
@@ -40,25 +47,26 @@ export const ActionsHeader = ({ maxWidth }: { maxWidth: number }) => {
         <span data-test-subj="unifiedDataTable_actionsColumnHeaderText">{actionsText}</span>
       ) : (
         <EuiIconTip
-          iconProps={{
-            'data-test-subj': 'unifiedDataTable_actionsColumnHeaderIcon',
-          }}
+          iconProps={{ 'data-test-subj': 'unifiedDataTable_actionsColumnHeaderIcon' }}
           type="info"
           content={actionsText}
         />
       )}
-      {/* Hidden measurement span */}
-      <span
-        ref={textRef}
-        css={css`
-          position: absolute;
-          visibility: hidden;
-          white-space: nowrap;
-          pointer-events: none;
-        `}
-      >
-        {actionsText}
-      </span>
+      <EuiResizeObserver onResize={measure}>
+        {(resizeRef) => (
+          <span
+            ref={resizeRef}
+            css={css`
+              position: absolute;
+              visibility: hidden;
+              white-space: nowrap;
+              pointer-events: none;
+            `}
+          >
+            {actionsText}
+          </span>
+        )}
+      </EuiResizeObserver>
     </ColumnHeaderTruncateContainer>
   );
 };