AssignmentValidatorEvents => Fix param name

types/Dojo/AssignmentValidatorEvents.ts

 interface AssignmentValidatorEvents {
     step: (name: string, message: string) => void;
     subStep: (name: string, message: string) => void;
-    endStep: (subStepName: string, message: string, error: boolean) => void;
+    endStep: (stepName: string, message: string, error: boolean) => void;
     endSubStep: (subStepName: string, message: string, error: boolean) => void;
     logs: (log: string, error: boolean, displayable: boolean) => void;
     finished: (success: boolean, exitCode: number) => void;