There's a merged pull request on the void-packages repository

common/build-style: remove go_get from Go style.
https://github.com/void-linux/void-packages/pull/28893

Description:
Fix Manual accordingly, and also fix indentation to be compatible with
nearby items.

The two packages which set this variable set it explicitly to "no", so
it wasn't relied upon. From its description, it was recommended only for
git packages, which by default don't fit Void's packaging guidelines.
Removing to avoid anyone coming to rely on it.

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#### General
- [ ] This is a new package and it conforms to the [quality requirements](https://github.com/void-linux/void-packages/blob/master/Manual.md#quality-requirements)

#### Have the results of the proposed changes been tested?
- [ ] I use the packages affected by the proposed changes on a regular basis and confirm this PR works for me
- [ ] I generally don't use the affected packages but briefly tested this PR

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