fix extra closing tag

Author: jjarvisp

src/pages/[platform]/build-a-backend/auth/concepts/passwordless/index.mdx

@@ -66,7 +66,6 @@ SMS-based authentication uses phone numbers as the identifier and text messages
 
 </InlineFilter>
 
-</InlineFilter>
 <InlineFilter filters={["swift"]}>
 
 {/*  */}