Create Task for running linting (markdownlint, …)

[vdemeester]

Expected Behavior

We should be testing and releasing Pipelines with Pipelines.

We should have a Task (and related Resources) defined that we can use to:

• Run our "linting" (markdownlint, …)

The Task

• Inputs:
  • git repo
• Outputs:
  • some kind of result info which can be passed to Create Task to update GitHub PR status #535
• Parameters:
  • some kind of gubernator endpoint info, will have to look into existing scripts to figure this out

Actual Behavior

We currently use prow.

This is where the current markdown linting is implemented: markdown_build_tests

• It uses https://github.com/markdownlint/markdownlint to link the markdown files
• It uses https://github.com/raviqqe/liche to lint the links in the markdown files

Note that these both only are applied to markdown files that have changed - we can leave that out of scope for this issue and apply the linting to all markdown files each run.

Additional Info

• Actually triggering this is not in scope for this issue, it's fine to test manually (we'll be linking these together in a later issue)

/cc @bobcatfish