[go] Fix a minor code-example bug

[koenbollen]

In the Zero-value fields section there is a minor mistake in the code examples, this change removes that.

PS: Thanks for making these styleguides publicly available!

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[gaal]

Thanks for the patch! This repository is managed internally so we cannot merge it directly. I'll get this integrated in our repo and have it pushed this week.

[koenbollen]

Thanks for the patch! This repository is managed internally so we cannot merge it directly. I'll get this integrated in our repo and have it pushed this week.

Yes, I saw that in the issue-template. Perfect! Thanks for the quick response!!

[gaal]

The fix has been applied upstream and pushed. Thanks again; I'm closing the pull request now.