[AIRFLOW-5398] Update contrib example DAGs to context manager

[eladkal]

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Description

Update example DAGs of EMR to context manager and bitshift composition.

Tests

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Documentation

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Code Quality

• Passes flake8

[ashb]

This change looks fine, but it's there a reason why just these example dags are updated rather than all? I feel there was an existing issue to update all dags to use the context manager.

[eladkal]

@ashb I worked with these specific examples didn't check the other ones
I'll make the changes for all examples in contrib

[eladkal]

@ashb Rebased again to solve conflicts

[codecov-io]

Codecov Report

Merging #5998 into master will decrease coverage by 0.03%.
The diff coverage is 0%.

@@            Coverage Diff             @@
##           master    #5998      +/-   ##
==========================================
- Coverage   80.09%   80.06%   -0.04%     
==========================================
  Files         596      609      +13     
  Lines       34872    35024     +152     
==========================================
+ Hits        27932    28042     +110     
- Misses       6940     6982      +42

Impacted Files	Coverage Δ
...ontrib/example_dags/example_databricks_operator.py	0% <0%> (ø)	⬆️
...dags/example_azure_container_instances_operator.py	0% <0%> (ø)	⬆️
...example_dags/example_kubernetes_executor_config.py	0% <0%> (ø)	⬆️
...ow/contrib/example_dags/example_qubole_operator.py	0% <0%> (ø)	⬆️
...ample_dags/example_emr_job_flow_automatic_steps.py	0% <0%> (ø)	⬆️
...trib/example_dags/example_azure_cosmosdb_sensor.py	0% <0%> (ø)	⬆️
...flow/contrib/example_dags/example_qubole_sensor.py	0% <0%> (ø)	⬆️
.../contrib/example_dags/example_dingding_operator.py	0% <0%> (ø)	⬆️
...contrib/example_dags/example_papermill_operator.py	0% <0%> (ø)
...low/contrib/example_dags/example_winrm_operator.py	0% <0%> (ø)	⬆️
... and 109 more

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[mik-laj]

@eladkal Can you extract an example from docs/howto/operator/papermill.rst file and improve it also?

[eladkal]

@mik-laj Done