Validation script argument handling inconsistent with readme documentation

### Expected Behaviour

JS validation script will run as documented in readme `npm run validateFile ./schema.yaml `

### Actual Behaviour
Fails due to mismatch between documentation and how args are handled in the code

### Reproduce Scenario (including but not limited to)
try running the script as documented

#### Steps to Reproduce

#### Platform and Version

#### Sample Code that illustrates the problem
`validateFile(process.argv[1], process.argv[2])`
should be
`validateFile(process.argv[3], process.argv[2])`
if it is to be consistent with docs. (wrong number arg numbers and out of order)

#### Logs taken while reproducing problem