move to chat message data models to Canopy from data models module

[acatav]

Problem

Role messages data models like UserMessage are not in canopy.models.data_models module where their base class is

Solution

Move this models to canopy.models.data_models

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update
• Infrastructure change (CI configs, etc)
• Non-code change (docs, etc)
• None of the above: (explain here)

Test Plan

Only moving classes around, should be captured by existing tests

[igiloh-pinecone]

LGTM!