[extension/jaegerremotesampling]: Remove featuregate switch from Thrift-gen with Proto-gen

[frzifus]

Component(s)

extension/jaegerremotesampling

Describe the issue you're reporting

Its a follow-up to #18485.

Right now there is a feature flag to use the Protobuf-gen struct used in the Jaeger 1.42 samplingStore impl. instead of the old Thrift-gen struct. With version 0.88.0 the Thrift-gen struct implementation should be dropped.

See:

• [extension/jaegerremotesampling] This extension may be broken after importing Jaeger v1.42 code #18047 (comment)

[github-actions]

Pinging code owners for extension/jaegerremotesampling: @jpkrohling @frzifus. See Adding Labels via Comments if you do not have permissions to add labels yourself.

[github-actions]

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[jpkrohling]

@frzifus, time to drop the feature flag?

[frzifus]

We agreed on dropping it after the next release, since it was not operational in the beginning.

[frzifus]

Done

• [receiver/jaeger] mark featuregates as stable #27636