Rename indices on partitions of runner tables

In !188902 (merged), we renamed indices on the routing table, but these changes weren't propagated to the table partitions. This means we'll need to write migrations with logic similar to https://gitlab.com/gitlab-org/gitlab/blob/3f452e9ea3abf87df316caf0c61b93ada734a904/db/post_migrate/20250422144359_drop_ci_runners_archived.rb#L14-72 for each of the partition tables of ci_runners and ci_runner_machines, so that the names no longer contain the old temporary names ci_runners_e59bb2812d and ci_runner_machines_687967fa8a.