Update the workflows to make the model-server image tags variable

[vprashar2929]

Currently, the existing GH workflows that are responsible for collecting and training the data make use of latest tag of the model-server image. When making a release, we have to use the release tag in the image. To do that we have to edit manually the workflow to make the model-server image point to the release version.
This should be handled by VERSION file where the version at the time of release is computed dynamically