[ts][player] Fixes 1233, list item min width needs to be set for Firefox on Windows.

spine-ts/player/css/spine-player.css

@@ -121,6 +121,7 @@
 	display: flex;
 	flex-direction: row;
 	width: 6px;
+	min-width: 6px;
 	height: 6px;
 	border-radius: 50%;
 	background: #fff;