Migrate to use aws-sdk for eks cluster creation and destruction

[gthao313]

Currently, we're using eksctl command to create clusters, and this method would bring limitations like less programmatic control. We should migrate testsys to use aws-sdk.

bottlerocket-test-system/bottlerocket/agents/src/bin/eks-resource-agent/eks_provider.rs

Lines 210 to 225 in 9c02930

	let status = Command::new("eksctl")
	.args([
	"create",
	"cluster",
	"-r",
	region,
	"--zones",
	&zones.clone().unwrap_or_default().join(","),
	"--version",
	&version_arg,
	"-n",
	cluster_name,
	"--nodes",
	"0",
	"--managed=false",
	])