Update gruvbox dark for better readability of ... (#4585)

... toolbar buttons

core/palettes/GruvBoxDark.tid

@@ -95,7 +95,7 @@ tag-foreground: #282828
 tiddler-background: <<colour background>>
 tiddler-border: <<colour background>>
 tiddler-controls-foreground-hover: #7c6f64
-tiddler-controls-foreground-selected: #7c6f64
+tiddler-controls-foreground-selected: <<colour primary>>
 tiddler-controls-foreground: #665c54
 tiddler-editor-background: #282828
 tiddler-editor-border-image: #282828
@@ -135,4 +135,4 @@ wikilist-button-remove: <<colour dirty-indicator>>
 wikilist-button-remove-hover: <<colour alert-background>>
 wikilist-droplink-dragover: <<colour dropzone-background>>
 wikilist-button-reveal: <<colour sidebar-tiddler-link-foreground-hover>>
-wikilist-button-reveal-hover: <<colour message-background>>
+wikilist-button-reveal-hover: <<colour message-background>>