adjust spacing within tag selector

1. Decrease the gap after colored tags.
2. In compact mode, decrease the splitter height.

chrome/content/zotero/components/tagSelector/tagSelectorList.jsx

@@ -105,7 +105,7 @@ class TagList extends React.PureComponent {
 		var row = 0;
 		let rowX = panePaddingLeft;
 
-		const separatorHeightCoefficient = 0.5;
+		const separatorHeightCoefficient = 0.25;
 		let separatorHeight = Math.round(rowHeight * separatorHeightCoefficient);
 		let shouldAddSeparator = false;
 		let hasColoredTags = !!this.props.tags[0]?.color;

scss/components/_tags-splitter.scss

@@ -1,4 +1,7 @@
 #zotero-tags-splitter {
     -moz-appearance: none;
     border-top: var(--material-border-quarternary);
+	@include compact {
+		min-height: 5px;
+	}
 }