Plugins: Remove externalCorePlugins feature toggle (#108386)

remove externalCorePlugins feature toggle

docs/sources/datasources/testdata/_index.md

@@ -126,13 +126,9 @@ This feature is experimental and requires Grafana version 10.3.0 or later.
 
 If you want to use a version of TestData different from the one shipped with Grafana, follow these steps:
 
-1. Enable the [feature toggle](https://grafana.com/docs/grafana/latest/setup-grafana/configure-grafana/feature-toggles/) `externalCorePlugins`.
 1. Set the configuration field `as_external` for the plugin to `true`. An example configuration would be:
 
    ```ini
-   [feature_toggles]
-   externalCorePlugins = true
-
    [plugin.grafana-testdata-datasource]
    as_external = true
    ```

docs/sources/setup-grafana/configure-grafana/_index.md

@@ -2655,8 +2655,6 @@ If `true`, propagate the tracing context to the plugin backend and enable tracin
 
 Load an external version of a core plugin if it has been installed.
 
-Experimental. Requires the feature toggle `externalCorePlugins` to be enabled.
-
 <hr>
 
 ### `[plugin.grafana-image-renderer]`

docs/sources/setup-grafana/configure-grafana/feature-toggles/index.md

@@ -42,7 +42,6 @@ Most [generally available](https://grafana.com/docs/release-life-cycle/#general-
 | `transformationsRedesign`              | Enables the transformations redesign                                                                                                                          | Yes                |
 | `awsAsyncQueryCaching`                 | Enable caching for async queries for Redshift and Athena. Requires that the datasource has caching and async query support enabled                            | Yes                |
 | `dashgpt`                              | Enable AI powered features in dashboards                                                                                                                      | Yes                |
-| `externalCorePlugins`                  | Allow core plugins to be loaded as external                                                                                                                   | Yes                |
 | `panelMonitoring`                      | Enables panel monitoring through logs and measurements                                                                                                        | Yes                |
 | `formatString`                         | Enable format string transformer                                                                                                                              | Yes                |
 | `kubernetesClientDashboardsFolders`    | Route the folder and dashboard service requests to k8s                                                                                                        | Yes                |