Feature union schemas

[fivetran-jamie]

PR Overview

This PR will address the following Issue/Feature:
#52 by merging in and adding to #53

This PR will result in the following new package version:

v0.11.0

Please provide the finalized CHANGELOG entry which details the relevant changes included in this PR:

Feature Update: Run Package on Unioned Connectors

• This release supports running the package on multiple Mixpanel sources at once! See the README for details on how to leverage this feature.
  • This was achieved through the introduction of new unioning macros.

Please note: This is a Breaking Change in that we have a added a new field, source_relation, that points to the source connector from which the record originated. This will require running a full refresh.

PR Checklist

Basic Validation

Please acknowledge that you have successfully performed the following commands locally:

• dbt run –full-refresh && dbt test
• dbt run (if incremental models are present) && dbt test

Before marking this PR as "ready for review" the following have been applied:

• The appropriate issue has been linked, tagged, and properly assigned
• All necessary documentation and version upgrades have been applied
• docs were regenerated (unless this PR does not include any code or yml updates) - after databricks passes
• BuildKite integration tests are passing
• Detailed validation steps have been provided below

Detailed Validation

Please share any and all of your validation steps:

devprodtest_incremental passes both steps

If you had to summarize this PR in an emoji, which would it be?

🥣

[fivetran-joemarkiewicz]

@fivetran-jamie this looks really good! I have a few change requests, but generally the code looks great and tested on the various iterations and didn't see any issues! Once these comments are addressed this should be ready for approval.

[fivetran-joemarkiewicz]

LGTM with responses to your comments

[fivetran-avinash]

@fivetran-jamie A few questions and comments before approval!

[fivetran-avinash]

lgtm