Allow testCaseId to default to codeRef which is not affected by process path as prefix

[CraigAndrew]

Proposed changes

This change will allow to opt out of prefixing the codeRef with the process file path e.g: "codebuild/sr123/test/wdio/features/home/HomePage.feature" and instead resolve to "As a US Customer User I should be able to view documentation" because some build servers like AWS codebuild uses arbitrary folder names each time and this breaks the linking of ReportPortal and all its cool features basically. Often we don't specify testCaseId and it gets set to the codeRef so the codeRef needs to be configurable to ensure it can be reliable across launches and not be hindered by CI build server including random path each time

[CraigAndrew]

This is what it looks like on AWS Codebuild causing a huge issue, pretty much disabling all useful ReportPortal functionality