Stabilize module pdata

[mx-psi]

Before stabilizing a module, an approver or maintainer must make sure that the following criteria are met:

• One RC release or more have been done of this module
  • Too many again :)
• No open issues or PRs in the module that would require breaking changes
  • Fix OTLP/JSON to use lowerCamelCase keys #6287
    • Suggested fix before 1.0 is to explicitly document that marshaling/unmarshaling adheres to the OTLP/JSON spec (see [pdata] Document that Marshalers/Unmarshalers use OTLP/JSON format explicitly #8974), which implies changing this is not a breaking change.
• No TODOs in the module code that would require breaking changes
  • To be fixed by moving the only remaining TODO to issue [pdata] Prevent RemoveIf memory leak by erasing truncated values in slices #8976, see PR [pdata] Remove TODO, move to issue #8977
• No deprecated symbols in the module
  • Nothing marked as deprecated, only the (internal) Deprecated structs https://github.com/search?q=repo%3Aopen-telemetry%2Fopentelemetry-collector+path%3A%2F%5Epdata%5C%2F%2F+Deprecated+language%3AGo&type=code
• No symbols marked as experimental in the module
  • Nope, nothing https://github.com/search?q=repo%3Aopen-telemetry%2Fopentelemetry-collector+path%3A%2F%5Epdata%5C%2F%2F+experimental+language%3AGo&type=code
• The module follows the Coding guidelines

Please also make sure to publicly announce our intent to stabilize the module on:

• The #otel-collector CNCF Slack Channel
  • https://cloud-native.slack.com/archives/C01N6P7KR6W/p1700583534633699
• The #opentelemetry CNCF Slack channel
  • https://cloud-native.slack.com/archives/CJFCJHG4Q/p1700583574227899
• A Collector SIG meeting (if unable to attend, just add to the agenda)
  • Discussed several times, most recently on November 15

To help other people verify the above criteria, please link to an RC release, the announcement and other links used to complete the above in a comment on this issue.

[mx-psi]

Labeling this as release:blocker to remind the release manager of the v0.90.0 release cycle that this and the featuregate module should be released as v1.0.0 on this release cycle. To proceed with the release, remove release:blocker and use 1.0.0 as the stable modset version.

This issue can be closed by the prep release PR.

[mx-psi]

Closed since we have released 1.0.0 🎉