components/email-input: fix the dark theme border by using gray-border

Author: LawnGnome

app/components/email-input.module.css

@@ -4,7 +4,7 @@
 
 .row {
     width: 100%;
-    border: 1px solid #d5d3cb;
+    border: 1px solid var(--gray-border);
     border-bottom-width: 0;
     padding: var(--space-2xs) var(--space-s);
     display: flex;