[AIRFLOW-6572] Move AWS classes to providers.amazon.aws package

[mik-laj]

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Issue link: AIRFLOW-6572

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• Description above provides context of the change
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[codecov-io]

Codecov Report

Merging #7178 into master will decrease coverage by 1.04%.
The diff coverage is 93.61%.

@@            Coverage Diff             @@
##           master    #7178      +/-   ##
==========================================
- Coverage   85.37%   84.32%   -1.05%     
==========================================
  Files         723      753      +30     
  Lines       39558    39685     +127     
==========================================
- Hits        33771    33466     -305     
- Misses       5787     6219     +432

Impacted Files	Coverage Δ
...rflow/contrib/sensors/sagemaker_training_sensor.py	0% <0%> (-100%)	⬇️
airflow/contrib/operators/s3_list_operator.py	100% <100%> (ø)	⬆️
.../contrib/operators/emr_create_job_flow_operator.py	100% <100%> (+8%)	⬆️
...ntrib/operators/emr_terminate_job_flow_operator.py	100% <100%> (+5%)	⬆️
.../contrib/operators/sagemaker_transform_operator.py	100% <100%> (+8.1%)	⬆️
airflow/providers/amazon/aws/hooks/glue_catalog.py	100% <100%> (ø)
airflow/contrib/sensors/emr_job_flow_sensor.py	100% <100%> (+4.54%)	⬆️
...flow/contrib/sensors/sagemaker_transform_sensor.py	100% <100%> (ø)	⬆️
...ample_dags/example_emr_job_flow_automatic_steps.py	100% <100%> (ø)	⬆️
...roviders/amazon/aws/sensors/sagemaker_transform.py	100% <100%> (ø)
... and 108 more

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