Linter: cannot define images for an exec pipeline

This error indicates you are using invalid configuration options for your pipeline. Specifically, you cannot define an image in an exec pipeline. Exec pipelines execute directly on the host and do not use Docker. If you want your pipeline steps to execute inside Docker containers you should be using docker pipelines, not exec pipelines.

kind: pipeline
type: exec
name: default

  - name: build
-   image: golang
    - go build
    - go test

Recommended reading if you are having difficulty understanding the concepts discussed in this thread.