remove unused css rules

src/vs/workbench/parts/debug/browser/media/debug.contribution.css

@@ -107,10 +107,6 @@
 	background: url('pause.svg') center center no-repeat;
 }
 
-.monaco-workbench .debug-action.attach {
-	background: url('attach.svg') center center no-repeat;
-}
-
 .monaco-workbench .debug-action.stop {
 	background: url('stop.svg') center center no-repeat;
 }

src/vs/workbench/parts/markers/browser/media/markers.css

@@ -18,11 +18,6 @@
 	border: 1px solid #ddd;
 }
 
-.monaco-action-bar .action-item.markers-panel-action-filter .filterIcon {
-	margin: 2px 0 0 4px;
-	background: url('filter.svg') center center no-repeat;
-}
-
 .markers-panel .markers-panel-container {
 	height: 100%;
 }