Support Slurm options in launch_fluent

[mkundu1]

>>> slurm = pyfluent.launch_fluent(scheduler_options={"scheduler": "slurm"})
>>> slurm
<ansys.fluent.core.launcher.launcher.SlurmFuture object at 0x2b9238af63b0>
>>> slurm.pending(), slurm.running(), slurm.done()
(True, False, False)  # before Fluent is launched
>>>  slurm.pending(), slurm.running(), slurm.done()
(False, True, False) # after Fluent is launched
>>> session = slurm.result()
>>> session.exit()
>>> slurm.pending(), slurm.running(), slurm.done()
(False, False, True)

[seanpearsonuk]

@mkundu1 We just need to be aware if there are potential conflicts with @hpohekar's branch.

[seanpearsonuk]

This is a good format for the PR description.