Structure containing the updated stack policy body. If you pass StackPolicyBody and StackPolicyURL, only
StackPolicyBody is used. If you want to update a stack policy during a stack update, specify an updated stack policy. For example,
you can include an updated stack policy to protect a new resource created in the stack update. If you do not specify a stack policy, the
current policy that is associated with the stack is unchanged.
Constraints:

C# |
public string StackPolicyBody { get; set; }