Bump cel-go to v0.27.0 to pick up the fix for context cancellation
error reporting that's breaking CI (see #138334).
Changes worth noting:
- cel-go switched from gopkg.in/yaml.v3 to go.yaml.in/yaml/v3,
so removed it from the gopkg.in/yaml.v3 unwanted references
- Dropped transitive dep github.com/stoewer/go-strcase
- Updated transitive dep github.com/antlr4-go/antlr/v4
- Pinned cel-go at v0.27.0 in hack/unwanted-dependencies.json
Kubernetes-commit: <drop>
