Extract common Python code into a Lambda Layer

[landonshumway-ia]

We are starting to hit an issue where code is being copy/pasted in multiple places across the project which long term will make this project difficult to maintain. To address this, the python code that is the same across all of our lambda functions needs to be extracted into a lambda layer, which will allow us to share the python code from one location without having to copy/paste it everywhere.

Acceptance Criteria:
Common config, utils, and schema files are moved into a common folder and deployed as a lambda layer.
Test logic is updated to use this common folder so the automated tests still work when deploying the project.