feat: add useHttpGet flag to S3 configuration

[razbroc]

Question	Answer
Bug fix	✖
New feature	✔
Breaking change	✖
Deprecations	✖
Documentation	✖
Tests added	✔
Chore	✖

This pull request introduces support for configuring the use of HTTP GET requests with S3 storage through a new useHttpGet/use_http_get option. The change is implemented across configuration files, environment variable templates, the main codebase, and tests to ensure the new option is properly handled and tested.

Configuration and environment variable support:

• Added useHttpGet to the S3 configuration in config/default.json and mapped it to the S3_USE_HTTP_GET environment variable in config/custom-environment-variables.json. [1] [2]
• Updated Helm chart templates and values (helm/templates/configmap.yaml, helm/values.yaml) to support and expose the useHttpGet option for S3 storage. [1] [2] [3]

Codebase enhancements:

• Extended the IS3Config and IS3Source interfaces to include the useHttpGet/use_http_get property, and updated the S3Source class to pass this property into the cache source definition. [1] [2] [3] [4]

Testing improvements:

• Updated integration and unit tests to register and verify the useHttpGet property in S3 configuration, including new test cases for layers with both true and false values. [1] [2] [3] [4]