Added missing camera methods to Snapshotter

[julianrex]

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• Write tests for all new functionality. If tests were not written, please explain why.
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Summary of changes

This PR adds 2 camera methods to Snapshotter to align with Android:

func coordinateBounds(for camera: CameraOptions) -> CoordinateBounds

func camera(for coordinates: [CLLocationCoordinate2D],
                       padding: UIEdgeInsets,
                       bearing: Double?,
                       pitch: Double?) -> CameraOptions

/cc @kiryldz

[neelmistry94]

mainly nits