Support manual creation for release status metrics via pipeline variables

What does this MR do and why?

For the release status metrics (delivery_release_monthly_status and delivery_release_patch_status), support separately creating them using manually triggered ops release/tools pipelines.

When we make changes to the functionalities of the metrics creation, or when we need to push a correcting metric, we currently create a temporary protected branch with the same changes, and create a pipeline (runbook). This process can be prone to errors and confusion. We should just support this functionality off of the default branch.

Only the maintainers of the repository can create these pipelines from the default branch (which is the same access as other protected branches), so the access scope stays the same as the above process.

We should also update that runbook after merging this MR to contain all the possible pipeline variables that release managers can use to manually trigger these pipelines.