Add include_stability config into semconv_grouped_attributes

[lmolkova]

We support exclude_stability but it's proven to be dangerous. The key scenario behind it is separating stable from non-stable signals.

exclude_stability: "experimental" is more prone to bugs (e.g. excluding "development" would bring a bunch of rc attributes and does not really make sense). What happened in open-telemetry/semantic-conventions#1777 is that we let attribute without stability in and it appeared as stable in Python and C++ since it was not experimental either.

If we used include_stability: ["stable"] it would be more robust.

We should consider going even further and just provide stable_only = true|false parameter.

[lmolkova]

Great suggestion from @jerbly in the chat

Second hole plug suggestion: We could change the logic of is_experimental to return true by default: https://github.com/open-telemetry/weaver/blob/main/crates/weaver_forge/src/extensions/otel.rs#L280-L292 (edited)