[chore] Add @jade-guiton-dd as a triager (#11730)

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#### Description

Promote @jade-guiton-dd to triager on behalf of
@open-telemetry/collector-maintainers.

- PRs reviewed:
https://github.com/open-telemetry/opentelemetry-collector/pulls?q=is%3Apr+reviewed-by%3Ajade-guiton-dd+
- PRs authored:
https://github.com/open-telemetry/opentelemetry-collector/pulls?q=is%3Apr+author%3Ajade-guiton-dd+
- Issues commented:
https://github.com/open-telemetry/opentelemetry-collector/issues?q=is%3Aissue+commenter%3Ajade-guiton-dd+
- Commits:
https://github.com/open-telemetry/opentelemetry-collector/commits?author=jade-guiton-dd

cc @open-telemetry/collector-triagers

README.md

@@ -164,6 +164,7 @@ Here is a list of community roles with current and previous members:
 
   - [Andrzej Stencel](https://github.com/andrzej-stencel), Elastic
   - [Damien Mathieu](https://github.com/dmathieu), Elastic
+  - [Jade Guiton](https://github.com/jade-guiton-dd), Datadog
   - Actively seeking contributors to triage issues
 
 - Emeritus Triagers: