[ES|QL] Enable in serverless (#180706)

## Summary

Enables ES|QL in serverless.

I am working on tests on a follow up PR
#181570

This is going to be merged when ES is being merged
elastic/elasticsearch-serverless#1588

---------

Co-authored-by: Kibana Machine <[email protected]>

config/serverless.yml

@@ -138,7 +138,7 @@ xpack.actions.queued.max: 10000
 # Disables ESQL in advanced settings (hides it from the UI)
 uiSettings:
   overrides:
-    discover:enableESQL: false
+    discover:enableESQL: true
 
 # Task Manager
 xpack.task_manager.allow_reading_invalid_state: false

packages/kbn-management/settings/setting_ids/index.ts

@@ -73,7 +73,7 @@ export const CONTEXT_DEFAULT_SIZE_ID = 'context:defaultSize';
 export const CONTEXT_STEP_ID = 'context:step';
 export const CONTEXT_TIE_BREAKER_FIELDS_ID = 'context:tieBreakerFields';
 export const DEFAULT_COLUMNS_ID = 'defaultColumns';
-export const DISCOVER_ENABLE_SQL_ID = 'discover:enableSql';
+export const DISCOVER_ENABLE_ESQL_ID = 'discover:enableESQL';
 export const DISCOVER_MAX_DOC_FIELDS_DISPLAYED_ID = 'discover:maxDocFieldsDisplayed';
 export const DISCOVER_MODIFY_COLUMNS_ON_SWITCH_ID = 'discover:modifyColumnsOnSwitch';
 export const DISCOVER_ROW_HEIGHT_OPTION_ID = 'discover:rowHeightOption';