First draft of adding contributing.md to each adapter repo

[McKnight-42]

resolves #

No issue currently

Description

Adding contributing.md files to each adapter

Checklist

• 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 updated the CHANGELOG.md and added information about my change to the "dbt-spark next" section.

[kwigley]

some tweaks, thanks for adding this to this repo

[kwigley]

I think we need a test.env.example for this repository, should we do that as part of this PR @McKnight-42?

[McKnight-42]

I think we need a test.env.example for this repository, should we do that as part of this PR @McKnight-42?

@kwigley I will look into getting that going thanks for pointing out it not being their, does it being in CircleCI and not GHA change anything? i think this is one of the only ones still over there.

[kwigley]

@McKnight-42 the test.env file is only used for testing locally, secrets for CircleCI and GHA are stored in those services. the test.env.example file can look like what is does for other database adapters to enable running integration tests locally 👍

[leahwicz]

This LGTM too but I would say make sure the changes you make in the Redshift file, you also make here

[leahwicz]

@McKnight-42 if the tests keep failing, it's ok to merge this one since this isn't a code change and instead flaky tests