pkg/jsonmessage: JSONMessage: remove deprecated ProgressMessage, ErrorMessage

[thaJeztah]

• relates to Refactor stream #2945
• relates to Do not require login unless 401 is received on push #1298

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depends on these fixes to be released in docker-py;

• integration/commit: Don't check for deprecated fields docker/docker-py#3203
• integration: adjust tests for omitted "OnBuild" docker/docker-py#3336
• tests/exec: expect 127 exit code for missing executable docker/docker-py#3290
• Set a dummy-version if none set, and remove unused APT_MIRROR build-arg docker/docker-py#3267
• image load: don't depend on deprecated JSONMessage.error field docker/docker-py#3307

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• ErrorMessage was deprecated in 3043c26
• ProgressMessage was deprecated in 597e0e6

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pkg/jsonmessage: JSONMessage: remove deprecated ProgressMessage, ErrorMessage

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[thaJeztah]

docker-py error could be legit, which means it's depending on the deprecated fields;

=================================== FAILURES ===================================
_____________________ ImageCollectionTest.test_load_error ______________________
tests/integration/models_images_test.py:96: in test_load_error
    with pytest.raises(docker.errors.ImageLoadError):
E   Failed: DID NOT RAISE <class 'docker.errors.ImageLoadError'>
------- generated xml file: /src/bundles/test-docker-py/junit-report.xml -------