Custom Endpoint not used during initial Account fetch

[redradrat]

Describe the bug
The initial account id check does not take into account a customized session config.

https://github.com/aws-controllers-k8s/runtime/blob/ae946aa1e0dd309db0064c2c347b724074725c60/pkg/config/config.go#L165-L167

Specifically the session creation here, without taking into account a custom awscfg is the issue:
https://github.com/aws-controllers-k8s/runtime/blob/ae946aa1e0dd309db0064c2c347b724074725c60/pkg/config/config.go#L149-L154

Steps to reproduce
Point the controller to a custom endpoint AWS_ENDPOINT_URL.

Expected outcome
The initial check should also take into account custom configured endpoint or other config.

Environment
Testing, Localstack(?)

• Kubernetes version
• Using EKS (yes/no), if so version? No
• AWS service targeted (S3, RDS, etc.) *

[ack-bot]

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Mark the issue as fresh with /remove-lifecycle stale.
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/lifecycle stale

[RedbackThomson]

Closing since we have merged aws-controllers-k8s/runtime#104