Add ci step to validate incorerct replacement fork

.drone.yml

@@ -257,6 +257,28 @@ volumes:
 
 ---
 kind: pipeline
+name: validate_go_mods
+
+platform:
+  os: linux
+  arch: amd64
+
+steps:
+  - name: validate_go_mods
+    image: rancher/dapper:v0.5.0
+    commands:
+      - dapper -f Dockerfile.test.mod.dapper
+
+    volumes:
+      - name: docker
+        path: /var/run/docker.sock
+volumes:
+  - name: docker
+    host:
+      path: /var/run/docker.sock
+
+---
+kind: pipeline
 name: manifest
 
 platform:

Dockerfile.test.mod.dapper

+ARG GOLANG=golang:1.16.2-alpine3.12
+FROM ${GOLANG}
+
+RUN apk -U --no-cache add bash jq
+ENV DAPPER_SOURCE /go/src/github.com/rancher/k3s/
+ENV HOME ${DAPPER_SOURCE}
+WORKDIR ${DAPPER_SOURCE}
+
+COPY ./scripts/test-mods /bin/
+
+ENTRYPOINT ["/bin/test-mods"]

scripts/test-mods

+#!/bin/bash
+set -e -x
+
+res=$(go mod edit --json | jq '.Replace[] | select(.Old.Path | contains("k8s.io/")) | .New.Path' | grep -v k3s-io | wc -l)
+if [ $res -gt 0 ];then
+  echo "Incorrect kubernetes replacement fork in go.mod"
+  exit 1
+else
+  exit 0
+fi