Use NuGet Trusted Publishing

[martincostello]

Switch to using GitHub OIDC for pushing packages to NuGet.org with Trusted Publishing.

@kevinchalet Could you update the repository configuration so this will work please?

Steps:

1. Create an environment called NuGet.org
2. Add a secret to the NuGet.org environment named NUGET_USER whose value is my NuGet.org username (it's not a secret, but I think it's better not to be hard-coded in the workflow 😃)
3. (Optionally) delete the NUGET_API_KEY secret

[kevinchalet]

@kevinchalet Could you update the repository configuration so this will work please?

Done on both repos. Let me know if you need anything else 😃

(Optionally) delete the NUGET_API_KEY secret

Once we're 100% sure NTP works as intended, I'll take care of that 👍🏻

[martincostello]

Once we're 100% sure NTP works as intended

I hope it does, as I used it to publish this 😅

[Copilot]

Pull Request Overview

Migrates the NuGet package publishing workflow from using a static API key to GitHub OIDC-based Trusted Publishing for enhanced security. This change eliminates the need for storing a long-lived NuGet API key as a repository secret.

• Adds GitHub environment configuration for NuGet.org with required OIDC permissions
• Integrates NuGet login action to obtain temporary API key through trusted publishing
• Updates package push step to use dynamically generated API key

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[martincostello]

Once we're 100% sure NTP works as intended, I'll take care of that 👍🏻

Looks like it's working.

[kevinchalet]

Looks like it's working.

Great! I deleted the API key on NuGet.org and removed the corresponding secret here 😃