filesystem: fix wrong helpstring for update_record_decoded

the helpstring of update_record_decoded mentions hex bytes for the data
parameter, but it should be mentioned as abstract json data like in
update_binary_decoded

Change-Id: Ibae2ab49054ac5dd6fcccddd28c98d886403dac9
Related: OS#4963
diff --git a/pySim/filesystem.py b/pySim/filesystem.py
index 82b4409..2023495 100644
--- a/pySim/filesystem.py
+++ b/pySim/filesystem.py
@@ -638,7 +638,7 @@
 
         upd_rec_dec_parser = argparse.ArgumentParser()
         upd_rec_dec_parser.add_argument('record_nr', type=int, help='Number of record to be read')
-        upd_rec_dec_parser.add_argument('data', help='Data bytes (hex format) to write')
+        upd_rec_dec_parser.add_argument('data', help='Abstract data (JSON format) to write')
         upd_rec_dec_parser.add_argument('--json-path', type=str,
                                         help='JSON path to modify specific element of record only')
         @cmd2.with_argparser(upd_rec_dec_parser)