Add config to autoset Helper Image ARCH and OS

What does this MR do?

When using the executorkubernetes, the Helper Image info are set with some default values and can be updated only using the node_selector feature. With this MR, we add a new configuration with will allow users to set the Helper Image info based on the underlying OS.

This property is disabled by default to not impact existing setup.

Why was this MR needed?

To allow users to, by e.g., pull an ARM64 helper image when Runner is already running on an ARM64 node.

What's the best way to test this MR?

TBD

What are the relevant issue numbers?

fixes #27768 (closed)