Add ds and swoole to extensions (#80)

Author: eiriksm

docs/introduction/extensions.mdx

@@ -24,6 +24,7 @@ curl
 date
 decimal
 dom
+ds
 exif
 fileinfo
 filter
@@ -71,6 +72,7 @@ SPL
 sqlite3
 sqlsrv
 standard
+swoole
 tokenizer
 uuid
 xml