fix count of empty BSC

queries/process_gsm.py

@@ -240,7 +240,9 @@ def gsm_analaysis(file_path: str):
     )
     df_site_per_lac = df_site_per_lac.drop_duplicates(subset=["code_lac"], keep="first")
 
-    GsmAnalysisData.total_number_of_bsc = len(gsm_df["BSC"].unique())
+    GsmAnalysisData.total_number_of_bsc = len(
+        gsm_df[gsm_df["BSC"].notna()]["BSC"].unique()
+    )
     GsmAnalysisData.total_number_of_cell = len(gsm_df["ID_BTS"].unique())
     GsmAnalysisData.number_of_site = len(gsm_df["site_name"].unique())
     GsmAnalysisData.number_of_cell_per_bsc = gsm_df["BSC"].value_counts()