* Remove language around uniqueness of event names within a domain
This came up in
https://github.com/open-telemetry/opentelemetry-collector-contrib/issues/14474
where it was highlighted that just `name` is not sufficient to provide
for uniqueness of a Kubernetes Event.
The attribute `event.domain` is only meant to be a logical separation
across different event systems, so it allows for similar looking names
in different domains but with a completely different purpose. However,
within each domain we don't have to have any uniqueness constraints on
the `name` and leave it to whatever is idiomatic to the particular event
system the domain represents.
Logs are transmitted via several common media, such as files and
iostreams. This PR establishes semantic conventions for describing the
file or iostream from which a log was read. Notably, these attributes
are not resource attributes, as the medium used to tranmit a log is not
considered to be the originator of the log.