[Glitch] Remove legacy decorators syntax

Port d1b057a0ac to glitch-soc

app/javascript/flavours/glitch/features/compose/components/header.jsx

@@ -45,7 +45,6 @@ const messages = defineMessages({
   },
 });
 
-export default @injectIntl
 class Header extends ImmutablePureComponent {
 
   static propTypes = {
@@ -134,3 +133,5 @@ class Header extends ImmutablePureComponent {
   }
 
 }
+
+export default injectIntl(Header);