Skip db migration in windows

lbrynet/db_migrator/dbmigrator.py

@@ -1,9 +1,12 @@
 import logging
+import os
 
 
 def migrate_db(db_dir, start, end):
     current = start
     old_dirs = []
+    if os.name == "nt":
+        return old_dirs
     while current < end:
         if current == 0:
             from lbrynet.db_migrator.migrate0to1 import do_migration