bump n2 version

[philipmac]

bump to prefect 2.18.1 to test updated FE

[annshress]

Prefect server is at different version: https://github.com/niaid/tf-hedwig-workflow-api/blob/main/Dockerfile

Also, there's another PR that matches. #467

As long as versions in both repo are the same, we are good.

[philipmac]

Prefect server is at different version: https://github.com/niaid/tf-hedwig-workflow-api/blob/main/Dockerfile

Also, there's another PR that matches. #467

As long as versions in both repo are the same, we are good.

I think the other PR is to version 2.16 - this is to 2.18
The current dev is running 2.18 - deployed last night, tested. This is was to test matching versions on HPC

[philipmac]

bumping to 2.19.1 instead - matching
https://github.com/niaid/tf-hedwig-workflow-api/commit/3ab8746198ca4766cfd4f61b435880c10b18dce8