* init release branch
* init 1.20 nightly tests
* drop 1.17 nightly tests for new release cycle
* drop 1.17 from test matrix
* Update nightly-test-integrations-1.20.x.yml
* Config changes to use backport-assistant with lts support
Co-authored-by: Michael Zalimeni <michael.zalimeni@hashicorp.com>
---------
Co-authored-by: claire labry <claire@hashicorp.com>
Co-authored-by: Michael Zalimeni <michael.zalimeni@hashicorp.com>