Remove --aws-config-env flag

[lander2k2]

The commands tptctl up and tptctl down currently have a --aws-config-env flag. The value from that flag is doing nothing as the function it is being passed to in https://github.com/nukleros/eks-cluster/blob/main/pkg/resource/config.go#L94 is not using it :/ (that should be fixed). However, the env vars are being used if present as documented in the https://github.com/aws/aws-sdk-go-v2/blob/main/config/config.go#L164.

We should eliminate the flag altogether and instead check for the existence of the env vars. If present in conjunction with the config profile and/or region flag, emit a warning as the environment will override those values.