Enable deterministic builds

[xPaw]

@JustArchi Archi do we need to add any other magic to improve the nuget?

[JustArchi]

@xPaw I only set deterministic to true in csproj, and add -p:ContinuousIntegrationBuild=true when building within CI, so pretty much what you did, but I prefer to not rely on CI being set in the env of the runners.

[xPaw]

CI env is documented here: https://docs.github.com/en/actions/learn-github-actions/variables#default-environment-variables

It's also commonly available on other systems.