set sort label for quick access elements to avoid symbols get removed…

… when they have the same label

org.eclipse.lsp4e/src/org/eclipse/lsp4e/operations/symbols/WorkspaceSymbolQuickAccessElement.java

@@ -46,6 +46,11 @@ public String getLabel() {
 		return LABEL_PROVIDER.getText(symbol);
 	}
 
+	@Override
+	public String getSortLabel() {
+		return getLabel() + " - " + this.idExtension; //$NON-NLS-1$
+	}
+
 	@Override
 	public ImageDescriptor getImageDescriptor() {
 		return ImageDescriptor.createFromImage(LABEL_PROVIDER.getImage(symbol));