packr2 does not respect go build's module path

[jeromegn]

I'm running into the following issue:

$ packr2 build -v --tags "json1" -ldflags="-X 'main.Version=1.0.0.0-dev'" -o bin/flyd ./cmd/flyd
// tons of logs
// ...
DEBU[2021-07-12T11:09:17-04:00] go build -v --tags json1 -ldflags=-X 'main.Version=1.0.0.0-dev' -o bin/flyd flyd
package flyd is not in GOROOT (/usr/lib/go/src/flyd)
Error: exit status 1

Note the path (./cmd/flyd) I'm trying to build is changed in the go build invocation from packr2.

Edit: my current workaround is to go build with the same arguments, but the correct path, right after this, ignoring the error.