This assumes go modules aren't used, and I'm not sure that will be possible in Go 1.13 as they want to deprecate GOPATH. I don't see any problem with forking and cloning, but if I'm missing something then please let me know the pitfalls of doing that.
go get -u in module mode will actually update all packages, whether you supply a package URL or not.
go get -u
There is talk about this tool which may be helpful, although I've never looked into it:
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