<!--Ex. Fixing a bug - Describe the bug and how this fixes the issue.
Ex. Adding a feature - Explain what this achieves.-->
#### Description
I didn't add the tag to any fields that have defaults set, since setting
these values to Go's zero value for that type would be a meaningful
configuration option that should appear in the config.
I think we could consider updates to the marshaler in the future to make
it possible to omit fields that have values matching the ones produced
by the `NewDefault[...]` functions, but that will be a more involved
effort we can tackle later.
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#### Link to tracking issue
Works toward
https://github.com/open-telemetry/opentelemetry-collector/issues/12191
Evan Bradley