[main up-port] Set opentelemetry span name in transformation filter (#368)

[ashishb-solo]

• Add setOperation patch

• Add changelog

• Transformation initial implementation

Should work but does not seem to at the moment

• Implement unit test for setting span name

• Update changelog

• Remove extra entry from changelog

• Do not override route.decorator.operation

• Add test for null route in callbacks

• Remove redundant call to setOperation

This is the default value that is set from the HCM - we do not need to write it a second time.

[solo-changelog-bot[bot]]

Issues linked to changelog: https://github.com/solo-io/gloo/issues/9848