fix(FloatButton): type error (#7632)

Author: Aaron-zon

components/float-button/interface.ts

@@ -20,7 +20,7 @@ export const floatButtonProps = () => {
     shape: stringType<FloatButtonShape>('circle'),
     tooltip: PropTypes.any,
     href: String,
-    target: stringType<'_self' | '_blank' | '_parent' | '_top'>(),
+    target: String,
     badge: objectType<FloatButtonBadgeProps>(),
     onClick: functionType<MouseEventHandler>(),
   };