Rename indices on ci_runner_taggings partitions

What does this MR do and why?

This MR renames the legacy names of the indices on the ci_runner_taggings partitions, so that they are more descriptive and better match the routing table's names. It is identical to the already-merged Rename indices on ci_runners partitions (!202279 - merged).

Changelog: other

References

Rename indices on partitions of runner tables (#548476 - closed)

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