[Security Solution][Detection Engine] fixes ES|QL metadata validation…

… error text (#188191)

## Summary

Removes deprecated square brackets from **metadata** operator in
validation error text

WAS

```
For example: FROM logs* [metadata _id, _version, _index]

```

AFTER

```
For example: FROM logs* metadata _id, _version, _index
```

Co-authored-by: Ryland Herrick <[email protected]>

x-pack/plugins/security_solution/public/detection_engine/rule_creation/logic/translations.ts

@@ -23,7 +23,7 @@ export const esqlValidationErrorMessage = (message: string) =>
 export const ESQL_VALIDATION_MISSING_METADATA_OPERATOR_IN_QUERY_ERROR = i18n.translate(
   'xpack.securitySolution.detectionEngine.esqlValidation.missingMetadataOperatorInQueryError',
   {
-    defaultMessage: `Queries that don’t use the STATS...BY function (non-aggregating queries) must include the "metadata _id, _version, _index" operator after the source command. For example: FROM logs* [metadata _id, _version, _index].`,
+    defaultMessage: `Queries that don’t use the STATS...BY function (non-aggregating queries) must include the "metadata _id, _version, _index" operator after the source command. For example: FROM logs* metadata _id, _version, _index.`,
   }
 );