Run rootReducer in tests

app/soapbox/components/__tests__/__snapshots__/emoji_selector-test.js.snap

@@ -16,7 +16,7 @@ exports[`<EmojiSelector /> renders correctly 1`] = `
     className="emoji-react-selector__emoji"
     dangerouslySetInnerHTML={
       Object {
-        "__html": "<img draggable=\\"false\\" class=\\"emojione\\" alt=\\"❤️\\" title=\\":heart:\\" src=\\"/emoji/2764.svg\\" />",
+        "__html": "<img draggable=\\"false\\" class=\\"emojione\\" alt=\\"❤\\" title=\\":heart:\\" src=\\"/emoji/2764.svg\\" />",
       }
     }
   />

app/soapbox/reducers/__tests__/instance-test.js

@@ -11,6 +11,7 @@ describe('instance reducer', () => {
         max_options: 4,
         min_expiration: 300,
       }),
+      version: '0.0.0',
     }));
   });
 });

app/soapbox/test_helpers.js

@@ -8,6 +8,7 @@ import { IntlProvider } from 'react-intl';
 import { BrowserRouter } from 'react-router-dom';
 import configureMockStore from 'redux-mock-store';
 import { Map as ImmutableMap } from 'immutable';
+import rootReducer from 'soapbox/reducers';
 
 // Mock Redux
 // https://redux.js.org/recipes/writing-tests/
@@ -18,7 +19,7 @@ export const mockStore = configureMockStore(middlewares);
 export const createComponent = (children, props = {}) => {
   props = ImmutableMap({
     locale: 'en',
-    store: mockStore(ImmutableMap()),
+    store: mockStore(rootReducer(ImmutableMap(), {})),
   }).merge(props);
 
   return renderer.create(