[762] Add a delay between scheduling Matrix configurations in Jenkins

[Kanaduchi]

Currently, all parallel configurations are scheduled simultaneously. This can lead to situations where Jenkins starts processing queued builds in an order different from the one specified in Execution order of builds.

Proposed solution: Implement the ability to configure a delay between scheduling configurations from a matrix into the Jenkins queue.

This setting would allow users to manually specify the delay interval between scheduling consecutive configurations.

Default value: 0
Unit: milis (or specify if needed)

This enhancement would help preserve the intended execution order and reduce unexpected build sequencing caused by Jenkins queue processing behavior.

Testing done

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[Kanaduchi]

@jenkinsci/matrix-project-plugin-developers Kindly ask you to review this PR