devel/ghq: Unbreak with go1.13

> Building for ghq-0.12.6

...

golang.org/x/xerrors

vendor/golang.org/x/xerrors/adaptor_go1_13.go:16:14: undefined: errors.Frame
vendor/golang.org/x/xerrors/format_go1_13.go:12:18: undefined: errors.Formatter
...

• Error code 2

• Unbreak by updating golang.org/x/xerrors to [1]

[1] https://github.com/golang/xerrors/commit/a985d3407aa71f30cf86696ee0a2f409709f22e1

PR: 240319
Submitted by: Dmitri Goutnik <dg@syrec.org>