Break apart CI workflows into composite actions

[mikealfare]

Edit: This PR is a pilot and will be broken down into workflow-specific PRs.

Problem

There are several places where the same steps are repeated across workflows. Additionally, while migrating from setup.py to pyproject.toml, there were some scenarios where migrating would be difficult because updating dependent centralized actions would adversely impact other repos.

Solution

If the workflows are broken apart into composite actions, then those actions could be reused across workflows. Additionally this may reduce the need for certain centralized actions.

Checklist

• I have read the contributing guide and understand what's expected of me
• I have run this code in development and it appears to resolve the stated issue
• This PR includes tests, or tests are not required/relevant for this PR
• This PR has no interface changes (e.g. macros, cli, logs, json artifacts, config files, adapter interface, etc) or this PR has already received feedback and approval from Product or DX

[github-actions]

Thank you for your pull request! We could not find a changelog entry for this change. For details on how to document a change, see the dbt-snowflake contributing guide.

[mikealfare]

This will happen as part of migrating to dbt-adapters