Fix color definition for Comments panel tree view icons (microsoft#185654)

Apparently Chrome is lenient about the missing closing parenthesis, so
this is not visibly broken in practice, but the Dev Tools show a warning
about an invalid property value.

Author: hermannloose

src/vs/workbench/contrib/comments/browser/commentsTreeViewer.ts

@@ -188,7 +188,7 @@ export class CommentNodeRenderer implements IListRenderer<ITreeNode<CommentNode>
 		if (node.element.threadState !== undefined) {
 			const color = this.getCommentThreadWidgetStateColor(node.element.threadState, this.themeService.getColorTheme());
 			templateData.threadMetadata.icon.style.setProperty(commentViewThreadStateColorVar, `${color}`);
-			templateData.threadMetadata.icon.style.color = `var(${commentViewThreadStateColorVar}`;
+			templateData.threadMetadata.icon.style.color = `var(${commentViewThreadStateColorVar})`;
 		}
 		templateData.threadMetadata.userNames.textContent = node.element.comment.userName;
 		templateData.threadMetadata.timestamp.setTimestamp(node.element.comment.timestamp ? new Date(node.element.comment.timestamp) : undefined);