Add the ability to run individual test methods for remote runs

[eamansour]

Story

As a tester running tests remotely on a Galasa service, I want to run just one method in isolation from within a test class, so that I can just check the result of one method, rather than waiting for all the methods to run.

Background

This is a potential nice-to-have feature that follows on from #2497.

The Galasa CLI tool's galasactl runs submit local command supports running individual test methods using the --methods flag. However, no equivalent functionality exists for running tests remotely on a Galasa service.

Would this feature be useful for users?

REST changes

{
  "tests": [
    "className": "string",
    "methodNames": [ // optional for users wanting to run a whole test class
        "string"
     ]
  ],
  "requestorType": "string",
  "requestor": "string",
...
}

CLI changes

Portfolio:

    - bundle: dev.galasa.ivts
      class: dev.galasa.ivts.core.CoreManagerIVT
      methods: testMethod1,testMethod2
      stream: ivts
      obr: ""
      overrides: {}
      gherkin: ""

galasactl runs submit --portfolio mytests.yaml

galasactl runs submit --stream myStream --class className --methods method1,method2

galasactl runs submit --stream myStream --class className --methods method1 --methods method2

Tasks

REST changes

• Deprecate old schema on openapi.yaml (but don't remove to avoid breaking users)
• Create new Test (name TBC) Object that represents a className and List of methodNames
• The payload for the POST to /runs/{groupId} should change to accept the new Object instead of a list of className strings (example above)

CLI changes

• Implement changes for runs submit
• Documentation / Release notes