dark: update border color of .ui.label

theme-github-dark.css

@@ -185,6 +185,9 @@ a.ui.label {
   color: #adbac7 !important;
   border-color: var(--color-secondary) !important;
 }
+.ui.label {
+  border-color: var(--color-secondary) !important;
+}
 .ui.menu .item {
   color: #adbac7;
 }