Fix chip styles in Checks UI for dark theme

Change-Id: I31d88a2ca7288cc48dc548aa504f42e5b3ad4be7

polygerrit-ui/app/styles/themes/dark-theme.ts

diff --git a/polygerrit-ui/app/styles/themes/dark-theme.ts b/polygerrit-ui/app/styles/themes/dark-theme.ts
index 4057f7f..072ca8f 100644
--- a/polygerrit-ui/app/styles/themes/dark-theme.ts
+++ b/polygerrit-ui/app/styles/themes/dark-theme.ts
@@ -44,9 +44,12 @@
       --warning-background: var(--orange-900);
       --info-foreground: var(--blue-200);
       --info-background: var(--blue-900);
+      --selected-foreground: var(--blue-200);
+      --selected-background: var(--blue-900);
       --info-deemphasized-foreground: var(--gray-700);
       --info-deemphasized-background: var(--primary-text-color);
       --success-foreground: var(--green-200);
+      --success-background: var(--green-900);
       --gray-foreground: var(--gray-100);
       --gray-background: var(--gray-900);
       --tag-background: var(--cyan-900);