Remove Geti workarounds for image rescaling on inference

[leoll2]

Because of a limitation in Model API, some workarounds were added in #5902 on Geti / OTX side to rescale the image intensity from [0-1] to [0-255] before forwarding it to Model API for inference.

After Model API adds the necessary logic to automatically infer the intensity scale from the model (open-edge-platform/model_api#520), the above workarounds shall be removed.