macos support & fix invoke-ccmsoftwareupdate using pssession

[theaquamarine]

• Remove the casts of Get-CimInstance output to [CimInstance[]] to allow the module to be used on non-Windows platforms that don't have [CimInstance]. Tested on macOS and Windows, but Linux should work too.
• Fix using Invoke-CCMSoftwareUpdate using a PSSession. PSSessions have to be used from non-Windows platforms, so this contributed to the above.

CimInstance and cim cmdlets are Windows-only, so anything using them elsewhere errors. Fortunately, most of the usage here isn't strictly required- most of the usage is casting the output from Get-CimInstance to [CimInstance[]], which is not usually required.

• On Windows, gcim or icm {gcim} return an Object[] containing CimInstances, so the casting is ensuring the result is an array, and changing the containing array's type.
• On macOS (and presumably Linux) icm {gcim} returns an Object[] containing PSObjects due to the lack of CimInstance
• Casts were change to [array] rather than [object[]] to be clearer that they're there to ensure the result is an array, rather than objects.

The only situation (I think) where a [CimInstance[]] specifically is required is CCM_SoftwareUpdatesManager's InstallUpdates() method, which is solved by doing the cast to [CimInstance[]] on the target machine via Invoke-Command, which will always have the type available if Invoke-CimMethod is going to work.

[CodyMathis123]

I like it!

Thank you very much for digging into this module :)