[Security Solution] [Attack discovery] Adds missing aria-label for th…

…e information button icon (elastic#206886)

### [Security Solution] [Attack discovery] Adds missing aria-label for the information button icon

This PR fixes an a11y issue reported in <elastic#206353>, where the information button icon, displayed while Attack discoveries are generated, was missing an `aria-label`.

This PR also updates an i18n translation in the same file, to add a missing word.

The _Before_ and _After_ screenshots below illustrate the fix, desk tested with Axe:

**Before**

![before](https://github.com/user-attachments/assets/a75d8b0c-2af7-44d0-9b10-fb961c5bd60e)

_Above: Before the fix, 1 Axe issue was detected while discoveries are generated_

**After**

![after](https://github.com/user-attachments/assets/5419f278-6963-47e2-bc99-35d5e6c2e64e)

_Above: After the fix, 0 Axe issues are detected while discoveries are generated_

#### Desk testing

The fix for this PR was desk tested locally via Axe.

Reproduction steps: <elastic#206353>

x-pack/solutions/security/plugins/security_solution/public/attack_discovery/pages/loading_callout/countdown/index.test.tsx

@@ -6,14 +6,14 @@
  */
 
 import moment from 'moment';
-
+import type { GenerationInterval } from '@kbn/elastic-assistant-common';
 import { act, render, screen } from '@testing-library/react';
 import React from 'react';
 
 import { Countdown } from '.';
 import { TestProviders } from '../../../../common/mock';
+import { INFORMATION } from '../translations';
 import { APPROXIMATE_TIME_REMAINING } from './translations';
-import type { GenerationInterval } from '@kbn/elastic-assistant-common';
 
 describe('Countdown', () => {
   const connectorIntervals: GenerationInterval[] = [
@@ -81,4 +81,14 @@ describe('Countdown', () => {
 
     expect(screen.getByTestId('timerText')).toHaveTextContent('00:59');
   });
+
+  it('renders an accessible information button icon', () => {
+    render(
+      <TestProviders>
+        <Countdown approximateFutureTime={null} connectorIntervals={connectorIntervals} />
+      </TestProviders>
+    );
+
+    expect(screen.getByRole('button', { name: INFORMATION })).toBeInTheDocument();
+  });
 });

x-pack/solutions/security/plugins/security_solution/public/attack_discovery/pages/loading_callout/countdown/index.tsx

@@ -15,14 +15,14 @@ import {
   useEuiTheme,
 } from '@elastic/eui';
 import { css } from '@emotion/react';
+import type { GenerationInterval } from '@kbn/elastic-assistant-common';
 import React, { useCallback, useEffect, useMemo, useState } from 'react';
 import moment from 'moment';
 
-import type { GenerationInterval } from '@kbn/elastic-assistant-common';
 import { useKibana } from '../../../../common/lib/kibana';
-import { getTimerPrefix } from './last_times_popover/helpers';
-
 import { InfoPopoverBody } from '../info_popover_body';
+import { getTimerPrefix } from './last_times_popover/helpers';
+import * as i18n from '../translations';
 
 const TEXT_COLOR = '#343741';
 
@@ -69,7 +69,9 @@ const CountdownComponent: React.FC<Props> = ({ approximateFutureTime, connectorI
   }, [approximateFutureTime]);
 
   const iconInQuestionButton = useMemo(
-    () => <EuiButtonIcon iconType="questionInCircle" onClick={onClick} />,
+    () => (
+      <EuiButtonIcon aria-label={i18n.INFORMATION} iconType="questionInCircle" onClick={onClick} />
+    ),
     [onClick]
   );
 

x-pack/solutions/security/plugins/security_solution/public/attack_discovery/pages/loading_callout/translations.ts

@@ -43,7 +43,7 @@ export const AI_IS_CURRENTLY_ANALYZING_RANGE = ({
   i18n.translate(
     'xpack.securitySolution.attackDiscovery.loadingCallout.aiIsCurrentlyAnalyzingRangeLabel',
     {
-      defaultMessage: `AI is analyzing up to {alertsCount} {alertsCount, plural, =1 {alert} other {alerts}} from {start} to {end} generate discoveries.`,
+      defaultMessage: `AI is analyzing up to {alertsCount} {alertsCount, plural, =1 {alert} other {alerts}} from {start} to {end} to generate discoveries.`,
       values: { alertsCount, end, start },
     }
   );
@@ -54,3 +54,10 @@ export const ATTACK_DISCOVERY_GENERATION_IN_PROGRESS = i18n.translate(
     defaultMessage: 'Attack discovery in progress',
   }
 );
+
+export const INFORMATION = i18n.translate(
+  'xpack.securitySolution.attackDiscovery.pages.loadingCallout.informationButtonLabel',
+  {
+    defaultMessage: 'Information',
+  }
+);