Although it seems as if Arsenal are gearing up for another big summer transfer window, there are some concerns that Profit and Sustainability Rules could limit spending. Mikel Arteta will perhaps require two or three marquee signings in order to go one step further in lifting the Premier League title next season. A new striker is thought to be on the agenda, with Newcastle United’s Alexander Isak and RB Leipzig’s Benjamin Sesko thought to be among the club’s favourites. But how much do Arsenal actually have to spend? According to the figures reported, Arteta spent around £200m last summer, but…