chore(deps): update terraform terraform-ibm-modules/cos/ibm to v8.21.0 (#630)

Author: terraform-ibm-modules-ops

examples/multi-resource-rule/main.tf

@@ -53,7 +53,7 @@ module "cbr_zone_vpc" {
 
 module "cos_instance_and_bucket" {
   source                        = "terraform-ibm-modules/cos/ibm"
-  version                       = "8.20.2"
+  version                       = "8.21.0"
   resource_group_id             = module.resource_group.resource_group_id
   region                        = var.region
   create_cos_instance           = true