Minor Ui bug fixes (#6295)

* PLT-6435 - Adjusting tooltip for add-channel-btn

* PLT-6404 - Fixing emoji reaction button on hover

webapp/components/sidebar.jsx

@@ -738,6 +738,7 @@ export default class Sidebar extends React.Component {
         let createPublicChannelIcon = (
             <OverlayTrigger
                 delayShow={500}
+                trigger='hover'
                 placement='top'
                 overlay={createChannelTootlip}
             >
@@ -755,6 +756,7 @@ export default class Sidebar extends React.Component {
             <OverlayTrigger
                 delayShow={500}
                 placement='top'
+                trigger='hover'
                 overlay={createGroupTootlip}
             >
                 <a

webapp/sass/layout/_post.scss

@@ -646,6 +646,7 @@
         .comment-icon__container,
         .post__reply,
         .post__remove,
+        .reacticon__container,
         .permalink-icon {
             visibility: visible;
         }