Setting overflow:hidden on lens-view elem

This prevents scrollbar flickering caused by Animation component
with 'slide-left' appearing.

Signed-off-by: alexfront <alex.andreev.email@gmail.com>

src/renderer/components/cluster-manager/cluster-manager.scss

@@ -8,6 +8,7 @@
   #lens-view {
     position: relative;
     grid-area: lens-view;
+    overflow: hidden;
 
     &.inactive {
       opacity: .85;