fix blockquote border line direction in RTL

src/app.css

@@ -53,11 +53,11 @@ math {
 }
 
 .markdown-prose {
-	@apply prose dark:prose-invert prose-blockquote:border-gray-100 prose-blockquote:dark:border-gray-800 prose-blockquote:border-l-2 prose-blockquote:not-italic prose-blockquote:font-normal  prose-headings:font-semibold prose-hr:my-4 prose-hr:border-gray-100 prose-hr:dark:border-gray-800 prose-p:my-0 prose-img:my-1 prose-headings:my-1 prose-pre:my-0 prose-table:my-0 prose-blockquote:my-0 prose-ul:-my-0 prose-ol:-my-0 prose-li:-my-0 whitespace-pre-line;
+	@apply prose dark:prose-invert prose-blockquote:border-s-gray-100 prose-blockquote:dark:border-gray-800 prose-blockquote:border-s-2 prose-blockquote:not-italic prose-blockquote:font-normal  prose-headings:font-semibold prose-hr:my-4 prose-hr:border-gray-100 prose-hr:dark:border-gray-800 prose-p:my-0 prose-img:my-1 prose-headings:my-1 prose-pre:my-0 prose-table:my-0 prose-blockquote:my-0 prose-ul:-my-0 prose-ol:-my-0 prose-li:-my-0 whitespace-pre-line;
 }
 
 .markdown-prose-xs {
-	@apply text-xs prose dark:prose-invert prose-blockquote:border-gray-100 prose-blockquote:dark:border-gray-800 prose-blockquote:border-l-2 prose-blockquote:not-italic prose-blockquote:font-normal  prose-headings:font-semibold prose-hr:my-0  prose-hr:border-gray-100 prose-hr:dark:border-gray-800 prose-p:my-0 prose-img:my-1 prose-headings:my-1 prose-pre:my-0 prose-table:my-0 prose-blockquote:my-0 prose-ul:-my-0 prose-ol:-my-0 prose-li:-my-0 whitespace-pre-line;
+	@apply text-xs prose dark:prose-invert prose-blockquote:border-s-gray-100 prose-blockquote:dark:border-gray-800 prose-blockquote:border-s-2 prose-blockquote:not-italic prose-blockquote:font-normal  prose-headings:font-semibold prose-hr:my-0  prose-hr:border-gray-100 prose-hr:dark:border-gray-800 prose-p:my-0 prose-img:my-1 prose-headings:my-1 prose-pre:my-0 prose-table:my-0 prose-blockquote:my-0 prose-ul:-my-0 prose-ol:-my-0 prose-li:-my-0 whitespace-pre-line;
 }
 
 .markdown a {