[Feature] Add support for snapshot hard deletes in spark/databricks

### Is this your first time submitting a feature request?

- [x] I have read the [expectations for open source contributors](https://docs.getdbt.com/docs/contributing/oss-expectations)
- [x] I have searched the existing issues, and I could not find an existing issue for this feature
- [x] I am requesting a straightforward extension of existing dbt functionality, rather than a Big Idea better suited to a discussion

### Describe the feature

Tests defined here _should_ pass: https://github.com/dbt-labs/dbt-adapters/pull/1378

We never properly added support for snapshot hard deletes (and probably other snapshot variations as well) in dbt-spark. This is blocking dbt-databricks as it inherits from spark.

### Describe alternatives you've considered

_No response_

### Who will this benefit?

_No response_

### Are you interested in contributing this feature?

_No response_

### Anything else?

_No response_