Implement EKS E2E Terraform Framework

[musa-asad]

Description of the issue

We aim to enhance our testing framework to support end-to-end testing of various helm-charts values and allow the use of custom branches for the agent, operator, and helm-charts repositories to enable testing of different configurations and prevent regressions to verify Kubernetes resource creation/deletion and metric emission.

Description of changes

Co-PR: aws/amazon-cloudwatch-agent#1445.

• Changes brought over from Add E2E EKS Terraform environment. #430 to be able to reference this repository from the GitHub workflow in the amazon-cloudwatch-agent package.
• Added new fields to MetaData and MetaDataStrings structs in environment/metadata.go to support EKS E2E testing parameters.
• Implemented registerEKSE2ETestData function to register new command-line flags for EKS E2E testing.
• Created new Terraform files (main.tf, providers.tf, variables.tf) in terraform/eks/e2e to set up EKS clusters for testing.
• Added eks_e2e test configuration in generator/test_case_generator.go. Separated it into testTypeToTestConfigE2E in order to avoid generating the non-E2E matrix files in the E2E workflow.
• Implemented ConfigureAWSClients function in util/awsservice/constant.go to allow custom region changes for AWS clients.

License

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

Tests

terraform apply --auto-approve -var="test_dir=../../../test/e2e/jmx" -var="agent_config=../../../test/e2e/jmx/resources/cwagent_configs/jvm_tomcat.json" -var="sample_app=../../../test/e2e/jmx/resources/sample_apps/tomcat-deployment.yaml"

Successfully deploys the CWA Operator, CWA, and Sample Application:

Also utilizes the correct images.

[okankoAMZ]

non-blocking comments. Looks good