docs: golang plugin doc missing information on cross-compiling
Metadata
Current evaluation
No evaluation has been recorded for this issue yet.
Issue body
*Please describe the question or issue you're facing with "Go plugin - Snapcraft 8.13.2 documentation".*
The "Environment variables" section states that:
> During build, this plugin sets `GOBIN` to `${CRAFT_PART_INSTALL}/bin`.
However, when I try to cross-compile on amd64, snapcraft pack errors out with:
```
Detailed information:
:: + go mod download all
:: + go install -p 8 ./...
:: go: cannot install cross-compiled binaries when GOBIN is set
Recommended resolution: Check the build output and verify the project can work with the 'go' plugin.
```
But when I clear it,
```yaml
build-environment:
- GOBIN: ""
```
then `pack` fails with:
```
FileNotFoundError: [Errno 2] No such file or directory: '/root/parts/<snap name>/install/usr'
```
---
*Reported from: https://documentation.ubuntu.com/snapcraft/8.13.2/common/craft-parts/reference/plugins/go_plugin/*
Evaluation history
No evaluation history available.