[PLT-7021] Add missing borders of emoji picker (#6897)

* add missing borders of emoji picker

* set input class `emoji-picker__search` border-width to zero

webapp/sass/components/_emoticons.scss

@@ -80,6 +80,8 @@
 
 .emoji-picker__search-container {
     position: relative;
+    border-top-style: solid;
+    border-top-width: 1px;
 
     .emoji-picker__search-icon {
         padding-left: 6px;
@@ -89,8 +91,7 @@
     }
 
     .emoji-picker__search {
-        border-width: 1px 0px 1px 0px;
+        border-width: 0px;
-        border-style: solid;
         padding: 2px 0 2px 25px;
         width: 100%;
         height: 25px;
@@ -108,6 +109,8 @@
     overflow-y: auto;
     padding: 0px 8px 8px 8px;
     position: relative;
+    border-top-style: solid;
+    border-top-width: 1px;
 
     .emoji-picker__category-header {
         font-size: 12px;

webapp/utils/utils.jsx

@@ -677,13 +677,10 @@ export function applyTheme(theme) {
         changeCss('.app__body .post-reaction:not(.post-reaction--current-user)', 'border-color:' + changeOpacity(theme.centerChannelColor, 0.25));
         changeCss('.app__body .post-reaction:not(.post-reaction--current-user)', 'color:' + changeOpacity(theme.centerChannelColor, 0.7));
         changeCss('.app__body .emoji-picker', 'color:' + theme.centerChannelColor);
-        changeCss('.app__body .emoji-picker, .app__body .emoji-picker__search-container .emoji-picker__search', 'border-color:' + changeOpacity(theme.centerChannelColor, 0.2));
+        changeCss('.app__body .emoji-picker', 'border-color:' + changeOpacity(theme.centerChannelColor, 0.2));
-        changeCss('.app__body .emoji-picker, .app__body .emoji-picker__items .emoji-picker__search-container .emoji-picker__search', 'border-color:' + changeOpacity(theme.centerChannelColor, 0.2));
+        changeCss('.app__body .emoji-picker__preview, .app__body .emoji-picker__items, .app__body .emoji-picker__search-container', 'border-top-color:' + changeOpacity(theme.centerChannelColor, 0.2));
         changeCss('.app__body .emoji-picker__items', 'background-color:' + changeOpacity(theme.centerChannelColor, 0.05));
-        changeCss('.app__body .emoji-picker__categories', 'border-bottom-color:' + changeOpacity(theme.centerChannelColor, 0.2));
         changeCss('.emoji-picker__category .fa:hover', 'color:' + changeOpacity(theme.centerChannelColor, 0.8));
-
-        changeCss('.app__body .emoji-picker__preview', 'border-top-color:' + changeOpacity(theme.centerChannelColor, 0.2));
         changeCss('.app__body .emoji-picker__category, .app__body .emoji-picker__category:focus, .app__body .emoji-picker__category:hover', 'color:' + changeOpacity(theme.centerChannelColor, 0.3));
         changeCss('.app__body .emoji-picker__category--selected, .app__body .emoji-picker__category--selected:focus, .app__body .emoji-picker__category--selected:hover', 'color:' + theme.centerChannelColor);
         changeCss('.app__body .emoji-picker__item-wrapper:hover', 'background-color:' + changeOpacity(theme.centerChannelColor, 0.8));