There should be a way to rebase+merge without creating a new pipeline

Context: I'm using the fast-forward merge flow.

When we rebase a MR through the UI, a new pipeline is started, but we would like for this to be optional. We don't always want to start a new pipeline. In fact, most times we just want to Rebase+Merge and accept the risk that after the rebase, the pipeline might fail.

I realize that we should always run a new pipeline after the rebase if we want to be 100% secure about not breaking the CI Pipeline, but in a large team with a lot of commits this isn't possible, since the main branch is moving too fast.

If a MR has a green pipeline, we want to be able to quickly and easily "Rebase+Merge" without creating a new pipeline on that side branch. We just want the pipeline to be created in the main branch.