code: public static <U> SimpleInstrumentationContext<U> whenCompleted(BiConsumer<U, Throwable> codeToRun) {
          return new SimpleInstrumentationContext<>(null, codeToRun);
      }
docs: Allows for the more fluent away to return an instrumentation context that runs the specified
  code on instrumentation step completion.
  
  @param codeToRun the code to run on completion
  @param <U>       the generic type
  
  @return an instrumentation context