Similar to #349 and associated PRs #433 and MicrosoftDocs/openapi-docs#141

We need to remove version 3.9 from:

• toml files
• github workflows
• documentation
• policy definition

Additionally, we should attempt and upgrade any dependency that was kept behind due to compatibility reason.

Since it's a standard practice in the ecosystem, this should be a feat: conventional commit (triggering a minor, not major version)

We'll also need to follow up in the documentation repository.