Deprecate description and env parameters in LightningCLI.__init__

[mauvilsa]

What does this PR do?

Fixes #15174

It includes the deprecations and the related suggestions in #15174 (comment). I also increased the minimum version of jsonargparse because otherwise mypy gives an error.

Does your PR introduce any breaking changes? If yes, please list them.

Three parameters are deprecated in LightningCLI.__init__ which should now be given through parser_kwargs:

• description
• env_prefix
• env_parse

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[victor-yon]

These changes solve the issue I submitted (#15174)