Deleting a Rule Script 
You can permanently remove a rule script from a development component.
Note
If a rule script is being used in the main flow or any other rule flow, you cannot delete it.
Locate the flow ruleset .
For more information, see Locating the Flow Ruleset
Expand the flow ruleset node, the Rule Scripts folder and in the context menu of a rule Script node, choose Delete.
In the dialog box that appears, choose Yes.