initial integration workflow for GHA

[emmyoop]

resolves #719

Description

Initial conversion of integration tests.

This partially follows the pattern followed in dbt-snowflake. Since this won't be running against an actual warehouse but in a container, there are no real savings to all the complexity added by the script.

It is untested but functioning to get us to a place where work can be split apart.

Checklist

• [ ] I have read the contributing guide and understand what's expected of me
• [ ] I have signed the CLA
• [ ] 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
• [ ] I have opened an issue to add/update docs, or docs changes are not required/relevant for this PR
• [ ] I have run changie new to create a changelog entry

[github-actions[bot]]

This PR has been marked as Stale because it has been open with no activity as of late. If you would like the PR to remain open, please comment on the PR or else it will be closed in 7 days.

[github-actions[bot]]

Although we are closing this PR as stale, it can still be reopened to continue development. Just add a comment to notify the maintainers.