ci: add test-vanilla-release & test-fork-release CI stages

Summary

• ci: add test-vanilla-release & test-fork-release CI stages + fix tests which were failing
• add ability to do #[tarantool::test(should_panic = cfg!(debug_assertions))]

Ensure that

• New code is covered by tests
• API is documented
• Changelog is up to date
• Version is bumped in the appropriate Cargo.toml files