Make build issue

[Rahul-Kaushik]

Getting below error after running the make build , post cloning the repo. The go.mod file is present in the same directory from which I am executing the make build.

@Rahul-Kaushik ➜ /workspaces/upf_p4_poc (main) $ make build
cp src/datapath/upf.p4 ngsdn-tutorial/p4src/main.p4
cd /workspaces/upf_p4_poc/ngsdn-tutorial && make p4-build
make[1]: Entering directory '/workspaces/upf_p4_poc/ngsdn-tutorial'
*** Building P4 program...
docker run --rm -v /workspaces/upf_p4_poc/ngsdn-tutorial:/workdir -w /workdir opennetworking/p4c:stable
p4c-bm2-ss --arch v1model -o p4src/build/bmv2.json
--p4runtime-files p4src/build/p4info.txt --Wdisable=unsupported
p4src/main.p4
*** P4 program compiled successfully! Output files are in p4src/build
make[1]: Leaving directory '/workspaces/upf_p4_poc/ngsdn-tutorial'
cp ngsdn-tutorial/p4src/build/bmv2.json build/
cp ngsdn-tutorial/p4src/build/p4info.txt build/
cd src/control/ && go build -o cp-upf main.go && mv cp-upf /workspaces/upf_p4_poc/build
go: github.com/antoninbas/p4runtime-go-client@v0.0.0-20201006021624-9212bb6aa549: missing go.sum entry for go.mod file; to add it:
go mod download github.com/antoninbas/p4runtime-go-client
go: github.com/antoninbas/p4runtime-go-client@v0.0.0-20201006021624-9212bb6aa549: missing go.sum entry for go.mod file; to add it:
go mod download github.com/antoninbas/p4runtime-go-client