Code Quality: Upgrade .gitignore to latest

[Lamparter]

Removed a few ignores such as the '.nupkg' ignore since this would conflict with the NuGet package in the 'lib' directory

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Before the change?

• .gitignore was the visual studio ignore at the time of project initialisation

After the change?

• Now the latest from the gitignore repo

This is a pretty minor code quality change but it's good to update files like these to future-proof the repo and prevent any accidents.

Pull request checklist

• Tests for the changes have been added (for bug fixes / features)
• Docs have been reviewed and added / updated if needed (for bug fixes / features)

Does this introduce a breaking change?

Please see our docs on breaking changes to help!

• Yes
• No

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[github-actions]

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[nickfloyd]

Thanks for this change... would you also mind updating actions/upload-artifact to v3 or v4 in dotnetcore.yaml to get CI ✅

[0x5bfa]

would you also mind updating actions/upload-artifact to v3 or v4 in dotnetcore.yaml to get CI ✅

Fyi, I did this in other pr. The pr that contains the move to src dir.
Anyways it won't conflict.

[Lamparter]

Yeah I think @nickfloyd just means they want to see the build result here 😅