Update documentation on DVT Hash Validation Throughput

[sundar-mudupalli-work]

Is your feature request related to a problem? Please describe.
This is a request to update "internal" documentation that we sometimes share with customers.
Specifically DVT Hash Validation Throughput

Describe the solution you'd like
This is an awesome document. Just a couple of small issues:

1. Since the document was created we have updated the Oracle driver we use (and Cx_oracle is obsolete). This simplifies the docker image as you don't need the Oracle instant client - unless you are using some thick client features.
2. Using 2GB of memory is great. Since CPU costs 10x memory - best to max out on memory - so use a 1vCPU - 4GB combination for lowest overall cost.

Sundar Mudupalli