Mistral >= 1.0.0 support

[adrienbanse]

This PR implements

• A second tracer for v1 of mistralai
• Automatic choice between the tracers if v0 or v1 is loaded
• A warning that v0 will soon be deprecated
• The documentation is extended with the second tracer, with warning that v0 will soon be deprecated

[samuelrince]

Thank you @adrienbanse for starting this work, I've made some changes:

1. Merged docs for Mistral AI v0 and v1

We now document Mistral AI v1 by default and I added a warning plus some annotations for Mistral AI v0. We should keep only one URL in the docs for mistral to avoid breaking references, plus we do not need to maintain extensive documentation for Mistral AI v0.

2. Changed Mistral AI tests to support v1 only

We must use Mistral AI v1 to develop, we only provide temporary support for the v0. We should test in priority feature on v1 for now.

3. Updated dependencies

PS: Strangely Cohere support was broken so I've updated it as well.

[samuelrince]

@adrienbanse I let you check and merge if you are okay! 🙏