[JENKINS-62065] Using keyframes rather than -webkit

No need to add browser prefixes since there is widespread support for this among browsers

war/src/main/less/base/style.less

@@ -1666,7 +1666,7 @@ table.progress-bar.red td.progress-bar-done {
   animation: fadeout 350ms ease-in 1 normal forwards;
 }
 
-@-webkit-keyframes fadein{
+@keyframes fadein{
   from{
     opacity: 0;
   }
@@ -1675,7 +1675,7 @@ table.progress-bar.red td.progress-bar-done {
   }
 }
 
-@-webkit-keyframes fadeout{
+@keyframes fadeout{
   from{
     opacity: 1;
   }