[low-code cdk] decouple parsing the yaml manifest from the declarative source implementation

[brianjlai]

What

The current way that YamlDeclarativeSource is structured and implemented couples parsing and resolving a YAML file and the implementation to run connector commands like read, spec, and check.

YAML parsing can really just function as a subclass of the underlying declarative implementation made up of the ConnectorDefinition manifest file. And this will allow us to start using the ManifestDeclarativeSource from the connector builder UI.

How

This is mostly moving the implementation to a new superclass that YamlDeclarativeSource will then inherit from. And YamlDeclarativeSource only needs to override the constructor to parse a YAML file and the remaining flow should be the same. The PR also looks large, but I reorganized the tests so a bulk of our testing and edge cases is against the already parsed manifest and only behavior relevant to yaml parsing is in the existing tests.

Recommended reading order

1. manifest_declarative_source.py
2. yaml_declarative_source.py
3. test_manifest_declarative_source.py
4. test_yaml_declarative_source.py

[brianjlai]

test no file change from a different package. will still publish

[brianjlai]

/publish-cdk dry-run=true

🕑 https://github.com/airbytehq/airbyte/actions/runs/3422632047
✅ https://github.com/airbytehq/airbyte/actions/runs/3422632047

[brianjlai]

/publish-cdk dry-run=false

🕑 https://github.com/airbytehq/airbyte/actions/runs/3422977643
✅ https://github.com/airbytehq/airbyte/actions/runs/3422977643