redpanda: assert go and helm equivalence

[chrisseto]

This commit adds a basic test for asserting that the Go code and helm templates generate equivalent manifests.

While gotohelm itself has many tests performing these assertions, the complexity of the redpanda chart warrants additional checks.

This commit also includes a handful of fixes for uncovered divergences:

• Use sigs.k8s.io/yaml in helmette to ensure consistent encoding/decoding
• Handle structs in helmette.Empty
• Fix an out of bounds truncation on a Secret name
• Add omityempty's to Tuning to match the sparse behavior of ToJSON in helm
• Add trailing newline to ToYaml to match helm
• Handle JSON key ordering weirdness in ToJSON