PAGOPA-1745 adding dynamic mechanism to retrieve station and broker

[FedericoRuzzier]

List of Changes

Setting up dynamic search for stations and brokers when retrieving the flows.

Motivation and Context

Change needed in order not to use one single station and broker (saved in env variables) to retrieve the various flows

How Has This Been Tested?

Manually

Screenshots (if appropriate):

Types of changes

• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist:

• [ ] My change requires a change to the documentation.
• [ ] I have updated the documentation accordingly.