Plugins: Expose promiseToDigest (#23249)

(cherry picked from commit ccb8187c)

public/app/features/plugins/plugin_loader.ts

@@ -36,6 +36,7 @@ import * as fileExport from 'app/core/utils/file_export';
 import * as flatten from 'app/core/utils/flatten';
 import * as ticks from 'app/core/utils/ticks';
 import { BackendSrv, getBackendSrv } from 'app/core/services/backend_srv';
+import { promiseToDigest } from 'app/core/utils/promiseToDigest';
 import impressionSrv from 'app/core/services/impression_srv';
 import builtInPlugins from './built_in_plugins';
 import * as d3 from 'd3';
@@ -134,6 +135,10 @@ exposeToPlugin('app/core/utils/file_export', fileExport);
 exposeToPlugin('app/core/utils/flatten', flatten);
 exposeToPlugin('app/core/utils/kbn', kbn);
 exposeToPlugin('app/core/utils/ticks', ticks);
+exposeToPlugin('app/core/utils/promiseToDigest', {
+  promiseToDigest: promiseToDigest,
+  __esModule: true,
+});
 
 exposeToPlugin('app/core/config', config);
 exposeToPlugin('app/core/time_series', TimeSeries);