STAC-25580: Update stepfunction.py

[Wolgo]

Explicitly only retrieve METADATA_ONLY

Not setting this value can result in errors if the agent does not have access to the KMS key or the kms:decrypt action, while the description is always discarded.

Instead, we can prevent these errors and remove the need to remove the description.

See: https://boto3.amazonaws.com/v1/documentation/api/latest/reference/services/stepfunctions/client/describe_state_machine.html

Step 1: Link to Jira issue

Step 2: Description of changes

Only retrieve METADATA to prevent errors on permissions that are needed to retrieve data that are discarded later on.

Step 3: Did you add / update tests for your changes in the right area?

• Unit/Component test
• Integration test

Step 4: I'm confident that everything is properly tested:

I got a PO / QA Approval by:

• Name

Step 5: Can we ship this feature to production?

• Yes, I'm proud of my work. Ship it! 🚢

[LouisParkin]

Thanks for this, and apologies for the long silence — it was not neglect alone. master required a status check (ci/gitlab/gitlab.com) from a GitLab pipeline that has since been archived, so this PR was literally unmergeable no matter who reviewed it. That is now fixed, and it needs only a review.

Tracked as STAC-25522 (the protection fix) and STAC-25580 (this change).

The reasoning holds up: the definition is fetched and then discarded, so includedData='METADATA_ONLY' removes both the wasted payload and the kms:decrypt requirement. Two things a reviewer will want to confirm — that our pinned botocore is new enough for includedData, and that the change gets forward-ported to stackstate-7.78.2, which is the branch that actually runs CI.

[Wolgo]

Hey @LouisParkin, as far as I see the whole stepfunction and AWS_topology has been removed in 7.78.2.
Sounds like you can just safely close the ticket (and this PR).