Fix NuGet Package API for $filter with Id equality

[tdesveaux]

Fixes issue when running choco info pkgname where pkgname is also a substring of another package Id.

Relates to #31168

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This might fix the issue linked, but I'd like to test it with more choco commands before closing the issue in case I find other problems if that's ok. I'm pretty inexperienced with Go, so feel free to nitpick things.

Not sure I handled this in the best way, so looking for feedback on if I should fix the underlying issue (nil might be a better default for Value?).