Remove pipeline_schedules_with_tags feature flag

What does this MR do and why?

This removes the pipeline_schedules_with_tags feature flag as it’s rolled out to production and enabled by default on self-hosted instances with %14.9. Now in %14.10, the feature can be fully released.

Related to #354421 (closed)

How to set up and validate locally

See the original MR !81476 (merged) (without the feature flag).

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