DataSourcePlugin: support custom tabs (#16859)

* use ConfigEditor

* add tabs

* add tabs

* set the nav in state

* remove actions

* reorder imports

* catch plugin loading errors

* better text

* keep props

* fix typo

* update snapshot

* rename tab to page

* add missing pages

public/app/routes/routes.ts

@@ -110,6 +110,7 @@ export function setupAngularRoutes($routeProvider, $locationProvider) {
     })
     .when('/datasources/edit/:id/', {
       template: '<react-container />',
+      reloadOnSearch: false, // for tabs
       resolve: {
         component: () => DataSourceSettingsPage,
       },