techdocs: stop exporting entity content empty state

Signed-off-by: MT Lewis <mtlewis@users.noreply.github.com>

plugins/techdocs/api-report-alpha.md

@@ -249,29 +249,6 @@ const _default: FrontendPlugin<
 >;
 export default _default;
 
-// @alpha (undocumented)
-export const TechDocsEntityContentEmptyState: ExtensionDefinition<{
-  config: {};
-  configInput: {};
-  output: ConfigurableExtensionDataRef<
-    React_2.JSX.Element,
-    'core.reactElement',
-    {}
-  >;
-  inputs: {
-    [x: string]: ExtensionInput<
-      AnyExtensionDataRef,
-      {
-        optional: boolean;
-        singleton: boolean;
-      }
-    >;
-  };
-  kind: 'element';
-  namespace: undefined;
-  name: 'entity-content-empty-state';
-}>;
-
 // @alpha (undocumented)
 export const techDocsSearchResultListItemExtension: ExtensionDefinition<{
   config: {

plugins/techdocs/src/alpha.tsx

@@ -185,8 +185,7 @@ const techDocsEntityContent = EntityContentBlueprint.makeWithOverrides({
   },
 });
 
-/** @alpha */
-export const TechDocsEntityContentEmptyState = createExtension({
+const TechDocsEntityContentEmptyState = createExtension({
   kind: 'element',
   name: 'entity-content-empty-state',
   attachTo: { id: 'entity-content:techdocs', input: 'emptyState' },