Add missing exits on exceptions.

Signed-off-by: Abdulkadir Furkan Şanlı <me@abdulocra.cy>

lb_import.py

@@ -12,6 +12,7 @@ def connect_client(auth_token):
         client.set_auth_token(auth_token)
     except BaseException:
         print("Unable to connect to ListenBrainz.")
+        sys.exit(1)
     return client
 
 
@@ -21,6 +22,7 @@ def open_export(export_file):
             export_json = json.load(read_file)
     except FileNotFoundError:
         print("File does not exist.")
+        sys.exit(1)
     return export_json