Source Exchange Rates: Refactor to use the CDK

[htrueman]

What

Part of #7242 story
Closes #7446

Pre-merge Checklist

Expand the relevant checklist and delete the others.

New Connector

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• Code reviews completed
• Documentation updated
  • Connector's README.md
  • Connector's bootstrap.md. See description and examples
  • docs/SUMMARY.md
  • docs/integrations/<source or destination>/<name>.md including changelog. See changelog example
  • docs/integrations/README.md
  • airbyte-integrations/builds.md
• PR name follows PR naming conventions
• Connector added to connector index like described here

Airbyter

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• New Connector version released on Dockerhub by running the /publish command described here

Updating a connector

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• Unit & integration tests added and passing. Community members, please provide proof of success locally e.g: screenshot or copy-paste unit, integration, and acceptance test output. To run acceptance tests for a Python connector, follow instructions in the README. For java connectors run ./gradlew :airbyte-integrations:connectors:<name>:integrationTest.
• Code reviews completed
• Documentation updated
  • Connector's README.md
  • Connector's bootstrap.md. See description and examples
  • Changelog updated in docs/integrations/<source or destination>/<name>.md including changelog. See changelog example
• PR name follows PR naming conventions
• Connector version bumped like described here

Airbyter

If this is a community PR, the Airbyte engineer reviewing this PR is responsible for the below items.

• Create a non-forked branch based on this PR and test the below items on it
• Build is successful
• Credentials added to Github CI. Instructions.
• /test connector=connectors/<name> command is passing.
• New Connector version released on Dockerhub by running the /publish command described here

Connector Generator

• Issue acceptance criteria met
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• The generator test modules (all connectors with -scaffold in their name) have been updated with the latest scaffold by running ./gradlew :airbyte-integrations:connector-templates:generator:testScaffoldTemplates then checking in your changes
• Documentation which references the generator is updated as needed.

[CLAassistant]

All committers have signed the CLA.

[htrueman]

/test connector=connectors/source-exchange-rates

🕑 connectors/source-exchange-rates https://github.com/airbytehq/airbyte/actions/runs/1394885426
✅ connectors/source-exchange-rates https://github.com/airbytehq/airbyte/actions/runs/1394885426
No Python unittests run