mention both Dashboards and endpoint (opensearch-project#7638)

* mention both Dashboards and endpoint

Old text said that Dashboards are a prerequisite for using PPL, and mentioned only the Query Workbench, not the _ppl endpoint.

Is it really true that Dashboards are a prerequisite? Or is it just the SQL plugin that is a prerequisite?

Signed-off-by: Stavros Macrakis <[email protected]>

* Update index.md

Signed-off-by: Naarcha-AWS <[email protected]>

---------

Signed-off-by: Stavros Macrakis <[email protected]>
Signed-off-by: Naarcha-AWS <[email protected]>
Co-authored-by: Naarcha-AWS <[email protected]>
Signed-off-by: Sander van de Geijn <[email protected]>

_search-plugins/sql/ppl/index.md

@@ -37,7 +37,15 @@ PPL filters, transforms, and aggregates data using a series of commands. See [Co
 
 ## Using PPL within OpenSearch
 
-To use PPL, you must have installed OpenSearch Dashboards. PPL is available within the [Query Workbench tool](https://playground.opensearch.org/app/opensearch-query-workbench#/). See the [Query Workbench]({{site.url}}{{site.baseurl}}/dashboards/query-workbench/) documentation for a tutorial on using PPL within OpenSearch.
+The SQL plugin is required to run PPL queries in OpenSearch. If you're running a minimal distribution of OpenSearch, you might have to [install the SQL plugin]({{site.url}}{{site.baseurl}}/install-and-configure/plugins/) before using PPL.
+{: .note}
+
+You can run PPL queries interactively in OpenSearch Dashboards or programmatically using the ``_ppl`` endpoint. 
+
+In OpenSearch Dashboards, the [Query Workbench tool](https://playground.opensearch.org/app/opensearch-query-workbench#/) provides an interactive testing environment, documented in [Query Workbench documentation]({{site.url}}{{site.baseurl}}/dashboards/query-workbench/).
+
+To run a PPL query using the API, see [SQL and PPL API]({{site.url}}{{site.baseurl}}/search-plugins/sql/sql-ppl-api/).
+
 
 ## Developer documentation