Replace JAEGER_DISABLED with OTEL_TRACES_SAMPLER

[yurishkuro]

Which problem is this PR solving?

• Part of https://github.com/jaegertracing/jaeger/issues/5385

Description of the changes

• Use OTEL env var that works with OTEL SDKs
• Update all docs starting from v1.48, when OTEL SDK were introduced

How was this change tested?

• Verified that starting all-in-one as below does not generate traces

  $ OTEL_TRACES_SAMPLER=always_off go run -tags=ui ./cmd/all-in-one

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