Makefile: Run go generate with GO111MODULE=on
Running `make update-assets` fails when the repo is under
`$GOPATH`. With `GO111MODULE=on`, running `go generate` works both
under and outside `$GOPATH`.
@@ -22,7 +22,7 @@ update-lk-submodule:
.PHONY: update-assets
update-assets:
- go generate ./...
+ GO111MODULE=on go generate ./...
.PHONY: build-slim
# Once we change CI code to build outside GOPATH, GO111MODULE can be removed, so
