fix(frontend) Match footer background to primary slate-700

Author: ken-blanchard

frontend/app/components/footer.tsx

@@ -6,7 +6,7 @@ export function Footer() {
   const { t } = useTranslation(['common']);
 
   return (
-    <footer id="wb-info" tabIndex={-1} className="bg-[#26374A]">
+    <footer id="wb-info" tabIndex={-1} className="bg-slate-700">
       <section>
         <h2 className="sr-only" id="accessibleSectionHeader1">
           {t('common:footer.header-accessible')}

frontend/tests/components/__snapshots__/footer.test.tsx.snap

@@ -3,7 +3,7 @@
 exports[`Footer > should render footer > expected html 1`] = `
 <div>
   <footer
-    class="bg-[#26374A]"
+    class="bg-slate-700"
     id="wb-info"
     tabindex="-1"
   >