Allign to the OpenCover format https://github.com/csMACnz/coveralls.net is using

Hi @GoEddie and thanks for your efforts.

There is a `fileid` attribute on each SequencePoint.
https://github.com/OpenCover/opencover/blob/e715910bb52e327ae6df059aeea71dff4b54ee50/main/OpenCover.Framework/Model/SequencePoint.cs#L35

I'm directly feeding it into the coveralls uploader https://github.com/csMACnz/coveralls.net, without using the reportgenerator.

For now, I use this Powershell snippet as a workaround, to make it working in my TeamCity Build.
```
[xml]$xmldocument = Get-Content -Path "./SQLCoverResults.xml"
Foreach ($class in ($xmldocument.CoverageSession.Modules.Module.Classes.GetElementsByTagName("Class"))) {
$fileref = $class.Methods.Method.FileRef.uid
foreach ($SequencePoint in $class.Methods.Method.SequencePoints.GetElementsByTagName("SequencePoint")) {
$SequencePoint.Setattribute("fileid",$fileRef)
}
}
$xmldocument.Save("./SQLCoverResults_2.xml");`
```

Not sure if you see this issue more here or in coveralls.net .

Thanks Oli

Compare SQLCoverResults.xml with the OpenCover SequencePoint model, especially the fileid attribute referenced in OpenCover.Framework/Model/SequencePoint.cs. Check the generated report against the coveralls.net uploader's expected format; done means the report can be consumed without the reported PowerShell workaround.

Written by the indexing model from the issue text.