Possibility to disable run deduplication

Since we have a monorepo, we often have to modify multiple stacks in a PR. Since Spacelift checks the project root of each individual commit and then runs the stacks that were modified.
If I now review a big PR, I have to look through each individual commit to see which one was the last to modify that file to see if it ran succesfully. This is not feasible.I can see two ways to fix that:

1. Whenever a file in some project root is modified, the stack will be run for every future commit of this PR (I call this sticky stacks) - merges from upstream are excluded. I don't think we can realize this with policies, as we would need some kind of state.

2. Just before merging, you can trigger stacks manually (e.g. with a command), even if the stack ran before. This currently does not work because of the stack deduplication.

The easiest way to fix it would be probably to make stack deduplication a setting or make a option to run a stack, with stack deduplication disabled, which can be used from the push policy.