I won't bet on this match and why? The main reason is manchester city has been qualified for the knock out stage. Pep may be using the secondary squad against leipzig and i don't even think that's a wise decision to bet on this match.
Manchester city will not be playing use the main squad. Pep will try to avoid the risk by putting the main players to play in this game. This game is not that important for city yet we will see that once line up will be announced.
We can also measure how strong city's squad compared with leipzig.
I don't think Pep will see this game as a casual one since they already qualified because they have drawn last two matches in Epl and that's not something a coach like Pep will ever take likely, he probably will use the main team and to get the mentality that man City is not regressing.