Remove transverse damper which is now in xfields

Author: Xavier Buffat

tests/test_transverse_damper.py

@@ -17,5 +17,4 @@
 from .yokoya import Yokoya
 from .read_headtail_table import read_headtail_file
 from .config_pipeline_for_wakes import config_pipeline_for_wakes
-from .beam_elements.transverse_damper import TransverseDamper