:book: switch markdownlint container to markdownlint-cli2

[tuminoid]

Switch markdownlint container to markdownlint-cli2. This CLI version supports the enable/disable rules in markdown files and allows us to ignore issues locally, not just globally.

• project-infra PR https://github.com/metal3-io/project-infra/pull/619 needs to merge for markdownlint here to pass

[tuminoid]

/hold Needs https://github.com/metal3-io/project-infra/pull/619 to merge first.

[elfosardo]

/approve feel free to unhold once mardownlint test is fixed

[metal3-io-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: elfosardo

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files: - ~~[OWNERS](https://github.com/metal3-io/ironic-image/blob/main/OWNERS)~~ [elfosardo] Approvers can indicate their approval by writing `/approve` in a comment Approvers can cancel approval by writing `/approve cancel` in a comment

[tuminoid]

Bumped to 0.9.0 release of the image from 2 days ago.

[tuminoid]

/retest Test new linter.

[tuminoid]

/override test-ubuntu-integration-main test-centos-integration-main

[metal3-io-bot]

@tuminoid: Overrode contexts on behalf of tuminoid: test-centos-integration-main, test-ubuntu-integration-main

In response to [this](https://github.com/metal3-io/ironic-image/pull/474#issuecomment-1908241352): >/override test-ubuntu-integration-main test-centos-integration-main Instructions for interacting with me using PR comments are available [here](https://git.k8s.io/community/contributors/guide/pull-requests.md). If you have questions or suggestions related to my behavior, please file an issue against the [kubernetes/test-infra](https://github.com/kubernetes/test-infra/issues/new?title=Prow%20issue:) repository.

[tuminoid]

/unhold Good to go.