Add extra steps to diagnostic to make output of hydrology/recipe_lisflood.yml usable by the LISFLOOD model

[JaroCamphuijsen]

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Tasks

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• Please use yamllint to check that your YAML files do not contain mistakes
• (Only if really necessary) Add any additional dependencies needed for the diagnostic script to setup.py, esmvaltool/install/R/r_requirements.txt or esmvaltool/install/Julia/Project.toml (depending on the language of your script) and also to package/meta.yaml for conda dependencies (includes Python and others, but not R/Julia)
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Modified recipe/diagnostic

• Update documentation for the recipe to the doc/sphinx/source/recipes folder
• Update provenance information if needed
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Closes #1736

[Peter9192]

Looks okay to me. 2 small comments for now. I'll approve after testing.

[Peter9192]

Seems to work fine!