Use new mattermost-govet (#18329)

```release-note
NONE
```

.gitlab-ci.yml

@@ -25,7 +25,6 @@ empty:
   image: $CI_REGISTRY/mattermost/ci/images/golangci-lint:v1.39.0-1
   stage: test
   script:
-    - GO111MODULE=off GOBIN=$PWD/bin go get -u github.com/mattermost/mattermost-govet
     - make config-reset
     - make check-style #todo MM_VET_OPENSPEC_PATH='$CI_PROJECT_DIR/mattermost-api-reference/v4/html/static/mattermost-openapi-v4.yaml'
   timeout: 60 mins