Try several encodings to read old WEO releases

Related to management#786 (closed)

weo_convert.py

@@ -65,9 +65,9 @@ def dataframe_from_csv(csv_file: Path, encoding_list):
     for encoding in encoding_list:
         try:
             return pd.read_csv(csv_file, delimiter="\t", encoding=encoding)
-        except:
+        except UnicodeDecodeError:
             pass
-    raise Exception(f"Can't find an encoding to read {csv_file!r}")
+    raise ValueError(f"Can't find an encoding to read {csv_file!r}")
 
 
 def process_csv_file(