docs: codeblock style fix after fuma upgrade (#4456)

docs/app/docs/[[...slug]]/page.tsx

@@ -75,7 +75,7 @@ export default async function Page({
 							return (
 								<CodeBlockTabs
 									{...props}
-									className="p-0 rounded-lg border-b bg-fd-secondary"
+									className="p-0 border-0 rounded-lg bg-fd-secondary"
 								>
 									<div {...props}>{props.children}</div>
 								</CodeBlockTabs>

docs/components/ui/code-block.tsx

@@ -149,6 +149,7 @@ export function CodeBlock({
 					!isTab && [bg, "rounded-none border border-x-0 border-b-0"],
 					"text-[13px] overflow-auto max-h-[600px] bg-fd-muted/50 fd-scroll-container",
 					viewportProps.className,
+					!title && "border-t-0",
 				)}
 				style={
 					{