chore: Upgrade flow (#1854)

* wip: upgrade flow

* chore: More sealed props improvements

* Final fixes

app/components/InputRich.js

@@ -8,13 +8,13 @@ import Editor from "components/Editor";
 import HelpText from "components/HelpText";
 import { LabelText, Outline } from "components/Input";
 
-type Props = {
+type Props = {|
   label: string,
   minHeight?: number,
   maxHeight?: number,
   readOnly?: boolean,
   ui: UiStore,
-};
+|};
 
 @observer
 class InputRich extends React.Component<Props> {