docs: Documentation update for OpenTelemetry and tracing

[cindy-peng]

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Fixes # 🦕

Please ignore Owlbot auto-commits for lint fixing and focus only on changes to https://github.com/googleapis/nodejs-logging/blob/bcf114654f6f16008741f85885230308aed5f318/.readme-partials.yml

Here is a preview for ReadMe rendering:

[generated-files-bot[bot]]

Warning: This pull request is touching the following templated files:

• README.md - README.md is managed by synthtool. However, a partials file can be used to update the README, e.g.: https://github.com/googleapis/nodejs-storage/blob/main/.readme-partials.yaml