add the optional version variable to the managed rules type

[sheenamt]

Changes proposed in this pull request:

This update allows the option to specify which version of the Managed Rules to use in the Web ACL. If nothing is specified, the default rule set will be used.

Example usage:

module "wafv2" {
source  = "trussworks/wafv2/aws"

managed_rules = [
    { "name" : "AWSManagedRulesCommonRuleSet",
      "override_action" : "count",
      "priority" : 10,
      "rule_action_override" : [],
      "vendor_name" : "AWS",
      "version" : "Version_2.0"
    }
  ]

[rpdelaney]

optional is magic

[rpdelaney]

Shipped in 2.9.0!