[docker-sonic-vs] always use separator ':' for GB_ASIC_DB, like ASIC_DB (#8806)

Author: jimmyzhai

platform/vs/docker-sonic-vs/database_config.json

@@ -60,17 +60,17 @@
         },
         "GB_ASIC_DB" : {
             "id" : 8,
-            "separator": "|",
+            "separator": ":",
             "instance" : "redis"
         },
         "GB_COUNTERS_DB" : {
             "id" : 9,
-            "separator": "|",
+            "separator": ":",
             "instance" : "redis"
         },
         "GB_FLEX_COUNTER_DB" : {
             "id" : 10,
-            "separator": "|",
+            "separator": ":",
             "instance" : "redis"
         },
         "CHASSIS_APP_DB" : {