Synchronize xppm and yppm

[romanc]

Description

Synchronize xppm.py and yppm.py. In particular, propagate an orchestration call from yppm.py to xppm.py.

There is script to generate yppm from xppm. That script was having outdated paths. Fixed that and and added other fixes such that it generates the expected output again. Also changed gsed to sed assuming people (or CI who I guess is eventually supposed to run the script) are running on non-BSD linux versions, which comes by default with the gnu flavor of sed.

How Has This Been Tested?

• Ran xppm and yppm tests locally
• Ran covert_xppm_yppm.sh locally which generated no changes to yppm.py.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas: N/A
• I have made corresponding changes to the documentation: N/A
• My changes generate no new warnings
• Any dependent changes have been merged and published in downstream modules: N/A
• New check tests, if applicable, are included: N/A
• Targeted model if this changed was triggered by a model need/shortcoming: N/A

[FlorianDeconinck]

LGTM

[romanc]

Just an idea (for a follow-up PR): I think it would be easy/trivial to create a github workflow that uses convert_xppm_yppm.sh to ensure xppm.py and yppm.py are in sync. We could even fit it in the linting one.

[FlorianDeconinck]

We definitely could. It's not really a priority and the PPM code will not change