Docker image build failed for PyTorch-Xeon

As part of building docker images for ResNet50-PyTorch-Xeon-Public and BERTLarge-PyTorch-Xeon-Public workloads, building PyTorch-Xeon intermediary image failed while setting up Conda environment.

https://github.com/intel/workload-services-framework/blob/23.2/stack/PyTorch-Xeon/Dockerfile.2.intel_public#L64

One of the dependency package _tornado_ where latest versions [stopped support for Python 3.7](https://www.tornadoweb.org/en/stable/releases/v6.3.0.html#general-changes) and throwing following error

> #10 27.09 ERROR: Could not find a version that satisfies the requirement tornado==6.3.2

Couple of options to resolve this

- Upgrade Python version to 3.8 or higher [here](https://github.com/intel/workload-services-framework/blob/23.2/stack/PyTorch-Xeon/Dockerfile.2.intel_public#L10)
- Fix tornado version to <= 6.2.0