python(chore): v0.10.0 prep

[solidiquis]

Summary

• Bumping to v0.10.0
• Removes experimental warnings for sift_client
• Adds deprecation warning for sift_py both in docs as well as on module initialization.

[alexluck-sift]

I recommend a few changes to the doc layout to support the deprecation and going stable of SiftClient:

• Update the mkdocs.yaml to place Sifit Client API first
• Update the hompage add deprecation warning on the old API and remove the experimental warning on the SiftClient
• Add a recommendation on version pinning and mention that we follow semantic versioning

See https://sift-stack.github.io/sift/python/pr-467/