Add chunk_model as parameter

[LouisLeNezet]

PR checklist

• This comment contains a description of changes (with reason).
• If you've fixed a bug or added code that should be tested, add tests!
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[LouisLeNezet]

I've retried on my cluster and the fulltest does now work without any issue with the modification on GLIMPSE2_chunk.

[atrigila]

The idea is good, some tests are missing in order to use sequential as the default chunk model for the pipeline. We should assert that it really works, otherwise, we will have the same problem when testing with AWS mega tests.