Support attribute_group-typed semantic conventions in semconv

[dashpole]

Is your feature request related to a problem? Please describe.

I'm interested in server.address, server.port, and url.scheme to fix open-telemetry/opentelemetry-collector-contrib#32814.

Describe the solution you'd like

The semconv packages don't appear to include attribute_group-typed conventions. I believe this is because the attribute_group type is not part of the semconvgen Makefile target:

opentelemetry-collector/Makefile

Lines 232 to 240 in cad2734

	# Generate semantic convention constants. Requires a clone of the opentelemetry-specification repo
	gensemconv: $(SEMCONVGEN) $(SEMCONVKIT)
	@[ "${SPECPATH}" ] || ( echo ">> env var SPECPATH is not set"; exit 1 )
	@[ "${SPECTAG}" ] || ( echo ">> env var SPECTAG is not set"; exit 1 )
	@echo "Generating semantic convention constants from specification version ${SPECTAG} at ${SPECPATH}"
	$(SEMCONVGEN) -o semconv/${SPECTAG} -t semconv/template.j2 -s ${SPECTAG} -i ${SPECPATH}/model/. --only=resource -p conventionType=resource -f generated_resource.go
	$(SEMCONVGEN) -o semconv/${SPECTAG} -t semconv/template.j2 -s ${SPECTAG} -i ${SPECPATH}/model/. --only=event -p conventionType=event -f generated_event.go
	$(SEMCONVGEN) -o semconv/${SPECTAG} -t semconv/template.j2 -s ${SPECTAG} -i ${SPECPATH}/model/. --only=span -p conventionType=trace -f generated_trace.go
	$(SEMCONVKIT) -output "semconv/$(SPECTAG)" -tag "$(SPECTAG)"