Most programs don't explicitly describe the warm-up because the individual's needs can be so different. My warm-up most days is a less-than-5 minute walk to the gym (three blocks away), about 5 minutes of different bodyweight movements/stretches/mobility work, and then get into my workout. 1-2 easier sets before getting up to the work sets is fine for me.
Somebody with specific issues, like a bad shoulder for example, might need a more thorough general warm-up every session. I do some extra hip mobility work on days I squat.
For that routine, a basic something to get the blood flowing (5-10 minutes tops, unless you have issues) should be fine, and then a few warm-up sets before the big exercises. You might not necessarily need many/any warm-up sets for the smaller exercises towards the end of the session.
There have been a bunch of articles talking about different warm-up approaches. This is a pretty good one: https://www.t-nation.com/training/no-nonsense-warm-ups-for-big-lifters