tweak context menu's text labels (#3306)

src/gui/src/css/style.css

@@ -1710,8 +1710,8 @@ span.header-sort-icon img {
 }
 
 .submenu-arrow {
-    width: 15px;
-    height: 15px;
+    width: 10px;
+    height: 10px;
     float: right;
 }
 
@@ -1719,6 +1719,10 @@ span.header-sort-icon img {
     display: none;
 }
 
+.context-menu-item .contextmenu-label {
+    height: 12px;
+}
+
 .context-menu-item-active .submenu-arrow {
     display: none;
     pointer-events: none;