fix docstring for get_image()

[ktdreyer]

In the compute API, the docstring for get_image() method's image_id parameter says "Node to run the task on." This description does not make sense. It looks like a bad copy-paste from the create_image() method's node parameter.

[ktdreyer]

(Looks like ReadTheDocs is not rendering :rtype NodeImage: :return: NodeImage instance on success. properly there either)

[Kami]

Thanks for reporting this - please feel free to open a PR with a fix :)

[stale]

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