Clarify stabilization plan does not just apply to attributes

[alanwest]

Clarification inspired by the following discussion open-telemetry/opentelemetry-dotnet#4766 (comment).

This text shows up in a lot of places. I can update them all, but wanted to get an initial review of the text here before I copy it everywhere. I assume this will not need to be updated in the specification repo once open-telemetry/opentelemetry-specification#3667 is merged.

@trask

[trask]

❤️

[Oberon00]

I think this is inconsistent with other wording we have elsewhere that says that semantic conventions only encompass the attribute keys and nothing else.

EDIT: Found it, it's this here: https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/versioning-and-stability.md#semantic-conventions-stability

[bryannaegele]

@Oberon00 I don't think that's accurate. That doc says Semantic Conventions defines the set of fields in the OTLP data model: and notes properties such as The span name under tracing. I don't see where it says it only encompasses attribute keys. Conventions for values are noted there.

[alanwest]

I don't see where it says it only encompasses attribute keys.

Me either... it seems this section in particular is pretty exhaustive.

@Oberon00 is there specific wording you're referring to that could be improved?

[Oberon00]

You are right it encompasses quite a bit. Even though it does not encompass attribute values or types, we can have stricter requirements for this special case anyway.

[alanwest]

Given the good number of approvals, shall I update the rest of the files in this PR with this updated text?

[trask]

Given the good number of approvals, shall I update the rest of the files in this PR with this updated text?

👍

Will review again, since now it's touching all other files