ReadGridded should support cropping geographically

[thorbjoernl]

Is your feature request related to a problem? Please describe.
Reading the entire griddeddata is quite memory intensive and discarding unneeded data (or ideally not reading it in in the first place) would be useful.

Describe the solution you would like to see

• Ideally, read calls would allow passing a bounding box and data outside of this bounding box is not read.

Additional context
Add any other context or screenshots about the feature request here.

[lewisblake]

Note: this will not work out of the box for non-lon-lat grids. So this PR will have to be limited in scope to only implement what xarray offers (e.g., .sel on longitude and latitude)