Update index.json file

index.json

 {
 	"version": "LTP06_1.0.0",
-	"release_date": "20220502",
+	"release_date": "20220609",
 	"descr": "Calibration package for LTP06",
 	"author": "Metis team",
 	"DOI": "",
@@ -120,7 +120,19 @@
 			"descr": "Vector describing the dynamic range of the VL detector response",
 			"validity": "True"
 		},
-		"bias": [],
+		"bias": [
+			{
+				"file_name": "solo_CAL_metis-vl-bias_20211215_V00.fits",
+				"obt_beg": 690710.91,
+				"tsensor": -30.41,
+				"nbin": 1,
+				"dit": 0.0,
+				"error": "solo_CAL_metis-vl-bias_20211215_V00_error.fits",
+				"source": "https://redmine.ict.inaf.it/projects/478/wiki/VL_Dark_and_Bias_Matrices",
+				"descr": "Bias map to be used for LTP05 - derived from STP181 instead of STP175",
+				"validity": "True"
+			}
+		],
 		"dark": [
 			{
 				"file_name": "map_dark_it1_dark30_dark15.fits",