[teachable] Add support for teachable based platform sites (closes #5451, closes #18150, closes #18272)

youtube_dl/extractor/extractors.py

@@ -1091,6 +1091,10 @@
 from .tastytrade import TastyTradeIE
 from .tbs import TBSIE
 from .tdslifeway import TDSLifewayIE
+from .teachable import (
+    TeachableIE,
+    TeachableCourseIE,
+)
 from .teachertube import (
     TeacherTubeIE,
     TeacherTubeUserIE,
@@ -1240,10 +1244,6 @@
     UplynkIE,
     UplynkPreplayIE,
 )
-from .upskill import (
-    UpskillIE,
-    UpskillCourseIE,
-)
 from .urort import UrortIE
 from .urplay import URPlayIE
 from .usanetwork import USANetworkIE