Script to check if entries in go.mod files are in sync

- ensure that the root go.mod and the module specific go.mod have the
  same `require` and `replace` directives for different dependencies.

Signed-off-by: Davanum Srinivas <davanum@gmail.com>

Makefile

@@ -425,6 +425,8 @@ verify-vendor: ## verify if all the go.mod/go.sum files are up-to-date
 	@(cd ${TMPDIR}/containerd/integration/client && ${GO} mod tidy)
 	@diff -r -u -q ${ROOTDIR} ${TMPDIR}/containerd
 	@rm -rf ${TMPDIR}
+	@${ROOTDIR}/script/verify-go-modules.sh api
+	@${ROOTDIR}/script/verify-go-modules.sh integration/client
 
 
 help: ## this help