Rename Hub class because it clashes cognitively with MonitoringHub (#1711)
Rename Hub class because it clashes cognitively with MonitoringHub (#1711)

There is now a MonitoringHub, containing a component called MonitoringRouter

Co-authored-by: Yadu Nand Babuji <d4d52b73e992a1e02c7e71afc690d71169073308@gmail.com>
Parsl/parsl,Parsl/parsl,Parsl/parsl,Parsl/parsl