[AIRFLOW-5011] Add typehints for GCP Vision operators

[mik-laj]

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Jira

• My PR addresses the following Airflow Jira issues and references them in the PR title. For example, "[AIRFLOW-XXX] My Airflow PR"
  • https://issues.apache.org/jira/browse/AIRFLOW-5011
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Description

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Tests

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Documentation

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Code Quality

• Passes flake8