v3.12.0

What's Changed

• ci: Add support to test Python 3.15.0 by @pvital in #852
• fix: Starlette test application. by @pvital in #854
• refactor(tracer): use Context instead of SpanContext by @pvital in #853
• refactor(span): Use of thekind parameter. by @pvital in #855
• chore(version): Bump version to 3.12.0. by @pvital in #856

Full Changelog: v3.11.1...v3.12.0