Dotnetcore 595

[sawilde]

Please provide the following information when submitting an pull request, where appropriate replace the [ ] with a [X]

The issue or feature being addressed

#595 .net core support

Details on the issue fix or feature implementation

initial test using -oldstyle flag

Confirm the following

• I have ensured that I have merged the latest changes from the main branch (or which ever branch is appropriate) from opencover/opencover
• I have run build create-release locally and have encountered no issues
• I agree to follow up on any work required to resolve any issues identified whilst my request is being accepted

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This change is