[chore] fix broken opencensus links CHANGELOG.md (#42566)

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Ex. Adding a feature - Explain what this achieves.-->
#### Description
pins now-removed component announcement links to the tagged version
where the components were announced
<!-- Issue number (e.g. #1234) or full URL to issue, if applicable. -->
#### Link to tracking issue
Fixes
https://github.com/open-telemetry/opentelemetry-collector-contrib/actions/runs/17561312676/job/49878257899?pr=42564

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#### Testing

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#### Documentation

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Author: jackgopack4

CHANGELOG.md

@@ -8665,7 +8665,7 @@ https://github.com/open-telemetry/opentelemetry-collector-contrib/issues/9278.
 - [`file` exporter](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/exporter/fileexporter) from core repository ([#3474](https://github.com/open-telemetry/opentelemetry-collector/issues/3474))
 - [`jaeger` exporter](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/v0.85.0/exporter/jaegerexporter) from core repository ([#3474](https://github.com/open-telemetry/opentelemetry-collector/issues/3474))
 - [`kafka` exporter](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/exporter/kafkaexporter) from core repository ([#3474](https://github.com/open-telemetry/opentelemetry-collector/issues/3474))
-- [`opencensus` exporter](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/exporter/opencensusexporter) from core repository ([#3474](https://github.com/open-telemetry/opentelemetry-collector/issues/3474))
+- [`opencensus` exporter](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/v0.34.0/exporter/opencensusexporter) from core repository ([#3474](https://github.com/open-telemetry/opentelemetry-collector/issues/3474))
 - [`prometheus` exporter](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/exporter/prometheusexporter) from core repository ([#3474](https://github.com/open-telemetry/opentelemetry-collector/issues/3474))
 - [`prometheusremotewrite` exporter](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/exporter/prometheusremotewriteexporter) from core repository ([#3474](https://github.com/open-telemetry/opentelemetry-collector/issues/3474))
 - [`zipkin` exporter](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/exporter/zipkinexporter) from core repository ([#3474](https://github.com/open-telemetry/opentelemetry-collector/issues/3474))
@@ -8677,7 +8677,7 @@ https://github.com/open-telemetry/opentelemetry-collector-contrib/issues/9278.
 - [`hostmetrics` receiver](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/receiver/hostmetricsreceiver) from core repository ([#3474](https://github.com/open-telemetry/opentelemetry-collector/issues/3474))
 - [`jaeger` receiver](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/receiver/jaegerreceiver) from core repository ([#3474](https://github.com/open-telemetry/opentelemetry-collector/issues/3474))
 - [`kafka` receiver](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/receiver/kafkareceiver) from core repository ([#3474](https://github.com/open-telemetry/opentelemetry-collector/issues/3474))
-- [`opencensus` receiver](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/receiver/opencensusreceiver) from core repository ([#3474](https://github.com/open-telemetry/opentelemetry-collector/issues/3474))
+- [`opencensus` receiver](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/v0.34.0/receiver/opencensusreceiver) from core repository ([#3474](https://github.com/open-telemetry/opentelemetry-collector/issues/3474))
 - [`prometheus` receiver](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/receiver/prometheusreceiver) from core repository ([#3474](https://github.com/open-telemetry/opentelemetry-collector/issues/3474))
 - [`zipkin` receiver](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/receiver/zipkinreceiver) from core repository ([#3474](https://github.com/open-telemetry/opentelemetry-collector/issues/3474))
 - [`bearertokenauth` extension](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/extension/bearertokenauthextension) from core repository ([#3474](https://github.com/open-telemetry/opentelemetry-collector/issues/3474))