cmd/go: go mod vendor ignore workspace

[fishy]

What version of Go are you using (go version)?

$ go version
go version go1.19 linux/amd64

Does this issue reproduce with the latest release?

Yes

What operating system and processor architecture are you using (go env)?

go env Output

$ go env
GO111MODULE=""
GOARCH="amd64"
GOBIN=""
GOCACHE="/home/fishy/.cache/go-build"
GOENV="/home/fishy/.config/go/env"
GOEXE=""
GOEXPERIMENT=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOINSECURE=""
GOMODCACHE="/home/fishy/.gopath/pkg/mod"
GONOPROXY=""
GONOSUMDB=""
GOOS="linux"
GOPATH="/home/fishy/.gopath"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/usr/lib/go-1.19"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/usr/lib/go-1.19/pkg/tool/linux_amd64"
GOVCS=""
GOVERSION="go1.19"
GCCGO="gccgo"
GOAMD64="v1"
AR="ar"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
GOMOD="/home/fishy/work/url2epub/cloudrun/go.mod"
GOWORK="/home/fishy/work/url2epub/go.work"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -Wl,--no-gc-sections -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build2972466680=/tmp/go-build -gno-record-gcc-switches"

What did you do?

$ git clone https://github.com/fishy/url2epub -b v0.4.0
$ cd url2epub/cloudrun
$ go mod vendor

What did you expect to see?

go files under cloudrun/vendor/go.yhsif.com/url2epub should be the same as the top level because I have this go.work at the top level:

$ cat go.work
go 1.19

use (
        .
        ./cloudrun
        ./debug
        ./rmapi/debug
)

What did you see instead?

url2epub/cloudrun/vendor/go.yhsif.com/url2epub is actually vendored at v0.3.1, as specified in cloudrun/go.mod.

[seankhliao]

Duplicate of #53904