Update EKS sample DAGs and docs

[ferruzzi]

Part of a project to standardize AWS provider package sample DAGs and documentation.

• Adds entries in the docs for the three EKS State Sensors
• All EKS sample DAGs are reformatted to be more consistent and to make the embedded snippets in the docs more approachable
• There is an example DAG that shows off how to use Jinja templates but it didn't actually use them for much, so I made that a better demo.

related: #21475
repost of #21508 after fixing the git bork.

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[ferruzzi]

having a jinja issue I need to figure out. If anyone knows the solution offhand, that would be appreciated, otherwise I'm reading up on it and will get it sooner or later.

File "/opt/airflow/airflow/providers/amazon/aws/example_dags/example_eks_templated.py", line 58, in <module>
      VPC_CONFIG = json.loads("{{ dag_run.conf['resources_vpc_config'] }}")

   << snip >>
    
json.decoder.JSONDecodeError: Expecting property name enclosed in double quotes: line 1 column 2 (char 1)

[github-actions]

The PR is likely OK to be merged with just subset of tests for default Python and Database versions without running the full matrix of tests, because it does not modify the core of Airflow. If the committers decide that the full tests matrix is needed, they will add the label 'full tests needed'. Then you should rebase to the latest main or amend the last commit of the PR, and push it with --force-with-lease.