[demo] Leverage set_semconv_span_name() for better span and http operation names (open-telemetry#2080)

* Use the Transform Processor `set_semconv_span_name()` to workaround span metrics cardinality explosion caused by high-cardinality span names

* Revert processor name to restore backward compatibility.

* Revert processor name to restore backward compatibility.

* Performances optimizations

* Performances optimizations

---------

Co-authored-by: Tyler Helmuth <12352919+TylerHelmuth@users.noreply.github.com>

Author: cyrille-leclerc

charts/opentelemetry-demo/Chart.yaml

@@ -1,7 +1,7 @@
 apiVersion: v2
 type: application
 name: opentelemetry-demo
-version: 0.40.3
+version: 0.40.4
 description: opentelemetry demo helm chart
 home: https://opentelemetry.io/
 sources:

charts/opentelemetry-demo/UPGRADING.md

@@ -5,6 +5,15 @@
 > another. If you need to upgrade the chart, you must first delete the existing
 > release and then install the new version.
 
+
+## To 0.40.4
+
+The `transform` processor now uses the `set_semconv_span_name()` function to
+reduce span metrics cardinality explosion caused by high-cardinality span names.
+See the [processor documentation](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/processor/transformprocessor#set_semconv_span_name)
+and [troubleshooting guide](https://github.com/open-telemetry/opentelemetry-collector-contrib/blob/main/connector/spanmetricsconnector/README.md#troubleshooting-span-metrics-high-cardinality)
+for details.
+
 ## To 0.40
 
 The product catalog has been moved to use a Postgres database. Custom products