[extractor/extractors] Remove non-existant imports

youtube_dl/extractor/extractors.py

@@ -940,12 +940,6 @@ from .xhamster import (
     XHamsterIE,
     XHamsterEmbedIE,
 )
-from .xiami import (
-    XiamiIE,
-    XiamiAlbumIE,
-    XiamiArtistIE,
-    XiamiCollectionIE
-)
 from .xminus import XMinusIE
 from .xnxx import XNXXIE
 from .xstream import XstreamIE