Remove unnecessary CI tempalte latest redirect feature flags

What does this MR do and why?

We added a couple of feature flags for redirecting to the latest CI templates for gradually rolling out them in 14.0 major update. However, some of them have not been cleaned up after the major update, that subsequently causes an issue like #342632 (closed).

This MR cleans up them according to the guideline.

Related #342632 (closed)

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