Add tableCaption to EuiBasicTable in log entry rate anomalies table (elastic#267503)

Closes: elastic#267502

Fixes `@elastic/eui/require-table-caption` ESLint violation in the log
entry rate anomalies table owned by `@elastic/obs-presentation-team`.

- Added `tableCaption` prop with i18n-translated string to
`EuiBasicTable` in
`x-pack/solutions/observability/plugins/infra/public/pages/logs/log_entry_rate/sections/anomalies/table.tsx`

```tsx
<EuiBasicTable
  tableCaption={i18n.translate('xpack.infra.logs.analysis.anomaliesTableCaption', {
    defaultMessage: 'Log entry anomalies',
  })}
  items={tableItems}
  ...
/>
```

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: alexwizp <20072247+alexwizp@users.noreply.github.com>
Co-authored-by: Alexey Antonov <alexwizp@gmail.com>

Author: Copilot

x-pack/solutions/observability/plugins/infra/public/pages/logs/log_entry_rate/sections/anomalies/table.tsx

@@ -207,6 +207,9 @@ export const AnomaliesTable: React.FunctionComponent<{
     <>
       <LoadingOverlayWrapper isLoading={isLoading}>
         <EuiBasicTable
+          tableCaption={i18n.translate('xpack.infra.logs.analysis.anomaliesTableCaption', {
+            defaultMessage: 'Log entry anomalies',
+          })}
           items={tableItems}
           itemId="id"
           itemIdToExpandedRowMap={expandedIdsRowContents}