Changes calculation of 5G handover.

plot_single_transmission_EM9190.py

                     ax00.axvline(index, ymin=0, ymax=1, color="skyblue")
 
         first = True
-        nr_handovers = transmission_df["NR5G_Cell_ID"].dropna().diff()
+        nr_handovers = transmission_df["NR5G_Cell_ID"].replace(0, np.NaN).dropna().diff()
         for index, value in nr_handovers.items():
             if value > 0:
                 if first: