Remove the operator.collector.default.config feature gate after promotion to stable

[Horiodino]

Component(s)

collector

Describe the issue you're reporting

Description

This is a follow-up to #4453, where the Collector default config feature gate (operator.collector.default.config) was promoted to stable.

As noted by @swiatekm in this comment the next step is to remove the feature gate entirely in the subsequent release, since it is no longer necessary once it reaches stable.

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