global.WorkflowApprovalUtils().reset Does Not Validate Parameters

The reset() method in WorkflowApprovalUtils will delete sysapproval_approver records related to the "task" parameter that is passed into it. However, that parameter is not validated and if it is not a valid GlideRecord the delete query that ends up being generated can match all sysapproval_approver records with an empty sysapproval field. This results in unwanted deletion of those records.

1. Ensure that sysapproval_approver table contains at least 1 record with an empty sysapproval field
2. from Scripts-Background, run "new WorkflowApprovalUtils().reset({sys_id : ""});"
 Expected: the sysapproval_approver records will not be deleted
 Actual: they are deleted

Other "invalid" parameters that can be passed into reset and may cause this issue depending on the JS engine mode used by the script execution are:
reset(null)
reset("")
reset()
reset(anyObjectWithoutASysIdProperty)
reset(new GlideRecord("task"))

The workaround is to add the following code to the beginning of the WorkflowApprovalUtils reset() method:

reset: function(/*GlideRecord*/ task, /*optional*/ comment) {
  //guard against an invalid task record
  if (JSUtil.nil(task) || JSUtil.nil(task.sys_id)) {
      gs.warn("Approval reset skipped because the task is invalid");
      return;
  }
...rest of the existing method code continues here