Add EFS filesystem ID into the connection secret

[ap-elmo]

What problem are you facing?

When trying to use writeConnectionSecretToRef for the filesystem resource, it doesn't output the filesystem ID into the connection secret. It ends up being an empty secret. Also when using publishConnectionDetailsTo, there is no secret created at all. We want to use the output of the filesystem id in some flux and kustomization patches.

What could help solve your problem?

Adding the filesystem id into the config.go for efs.

I am going to try contribute back and create a PR.