[Feature] Support session_token parameter with IAM User Auth

[colin-rogers-dbt]

Is this your first time submitting a feature request?

• I have read the expectations for open source contributors
• I have searched the existing issues, and I could not find an existing issue for this feature
• I am requesting a straightforward extension of existing dbt-redshift functionality, rather than a Big Idea better suited to a discussion

Describe the feature

Update IAM User auth: https://github.com/dbt-labs/dbt-redshift/blob/main/dbt/adapters/redshift/connections.py#L218

Acception a sesion_token parameter to allow for the use of temporary IAM credentials

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

[amychen1776]

closing this because we aren't doing it