use 65km top in amip

[szy21]

Purpose

Moves model top to 65km in amip configs. For the coarse resolution one I have to increase the number of levels to have enough levels in the sponge to stabilize it, and as a result I reduce t_end. It is stable for a year: https://buildkite.com/clima/climacoupler-coarse-nightly-amip/builds/124. It may still be finicky and I may need to fine-tune the grids in the future.

To-do

Content

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• I have read and checked the items on the review checklist.

[szy21]

The model top pressure goes below 1Pa, so let me think about it before merging. Here is July average pressure near south pole.