Apply overlays to manage notebook specific dependencies

[MichaelClifford]

There are two separate downstream ML tasks that we which to apply to our mailing list data through the analysis notebooks. However, each of these tasks rely on packages that have incompatible transitive dependencies. In short, globally defined requirements for this repo will no longer work. For specific details on the incompatible packages please see #68.

To address this issue, we should apply some of the Thoth tooling and use overlays to provide distinct requirements for each notebook. Following this tutorial should provide the instructions to set up the repo this way.

Acceptance Criteria:

• There is an overlays directory which contains notebook specific dependencies.
• Upate .aicoe.yaml to use overlays build for ci testing. Example
• ! pip install <pkg> statements are removed from all notebooks.

[aakankshaduggal]

/assign @aakankshaduggal

[isabelizimm]

/assign @isabelizimm