fix(eap-outcomes): Add trace ID and timestamp to dedup key

[untitaker]

ref STREAM-881

[linear-code]

STREAM-881 Investigate duplicate spans appearing after buffered-segments

[MeredithAnya]

@untitaker can you add

if item_type != TraceItemType::Span {
    return false;
}

in the is_duplicate? I want to see how much that lightens the load on the consumers, since if we can run few consumers we get better deduping

[cursor]

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