[Qiskit Ecosystem] Add an ecosystem.json file

[mickahell]

Summary

In order to pass the check on the Qiskit Ecosystem the proejct need an Ecosystem file called ecosystem.json.
This file is needed as soon as their are customization, here its the repo the tests are launching and the test requirements file.

Details

• Create ecosystem.json
• Dry run of Ecosystem check job run

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Closes #165
Related to Qiskit/ecosystem#202

[mickahell]

Hi @cqc-melf :)
I'm a Qiskit Advocate contributor to the Qiskit Ecosystem. Your project is actually a member but don't pass our checks anymore. Here a PR with a simple file to make it pass.
I run a dry run of the Ecosystem checks with the file and they now passed, you can find it here --> job run