Fix fixed element in spin

close #10196

components/spin/style/index.less

@@ -87,10 +87,7 @@
 
     /* autoprefixer: off */
     filter: ~"progid\:DXImageTransform\.Microsoft\.Blur(PixelRadius\=1, MakeShadow\=false)";
-    // workround for a strange style bug in safari:
-    // https://github.com/ant-design/ant-design/issues/4622
-    // have no clue why this works
-    -webkit-transform: translateZ(0);
+
     &:after {
       content: '';
       position: absolute;