[Tech debt] Add scheduled testing on protected branches

[mikealfare]

Is this your first time submitting an issue in dbt-athena?

• I have searched the existing issues, and I could not find an existing issue for this feature

Describe your request/question

We should add scheduled testing, as is done on other adapters. This ensures that we don't accidentally break something with things like automation that have override permissions. It also checks for shifting transient dependencies or dependencies that don't follow semantic versioning (intentionally or unintentionally).

Anything else?

No response