test: go back to AL2 image in tf integ tests

[valerena]

We tried to move to an AL2023 image for an Image function on Terraform tests, when updating to Python 3.9, but the AppVeyor environment had some problems. So let's go back to the AL2 base image and install Python 3.9 in a different way.

Which issue(s) does this change fix?

Why is this change necessary?

• AL2023 image had some network issues in AppVeyor environment, so we prefer to continue using AL2 image.

How does it address the issue?

What side effects does this change have?

Mandatory Checklist

PRs will only be reviewed after checklist is complete

• Add input/output type hints to new functions/methods
• Write design document if needed (Do I need to write a design document?)
• Write/update unit tests
• Write/update integration tests
• Write/update functional tests if needed
• make pr passes
• make update-reproducible-reqs if dependencies were changed
• Write documentation

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.