Add a Dagger integration section and cleanup Ecosystem CICD docs page

[jpadams]

Description

There is a Dagger integration for Trivy that we want to share through the docs page, so I made an update. In the course of updating the page, I noticed that the Azure DevOps content was stuck in the middle of the GitHub Actions content, so I moved that out to stand alone. I also noticed that integrations were using H2 (##) markdown, but the Buildkite entry was using H3 (###), so I fixed that to make things consistent.

Link

https://github.com/aquasec/trivy/blob/main/docs/ecosystem/cicd.md

Suggestions

https://github.com/jpadams/trivy/blob/cicd-md-cleanup-add-dagger/docs/ecosystem/cicd.md

[itaysk]

thanks for adding it!

[jpadams]

@AnaisUrlichs and @knqyf263

Is a manual deploy of these changes required?
#5608

[knqyf263]

You can see the change in the dev version, not latest.
https://aquasecurity.github.io/trivy/dev/ecosystem/cicd/

It is not versioned until the next version is released.