Adding expand icon for RHS (#3386)

* Adding expand icon for RHS

Fixing errors

Adding back getTeamInviteLink with better functionality for mobile

Adding vertical align to post__link

Updating improvements for expand RHS stuff

* Improving transition on mobile

* Removing irrelevant changes

webapp/sass/layout/_navigation.scss

@@ -72,6 +72,7 @@
                 color: $white;
                 display: inline-block;
                 font-weight: 600;
+                line-height: 47px;
                 margin-right: 5px;
                 max-width: calc(100% - 200px);
                 overflow: hidden;