Update instrumentation config behavior to return empty object when not set

Author: zeitlinger

CHANGELOG.md

@@ -46,6 +46,9 @@ release.
   ([#4802](https://github.com/open-telemetry/opentelemetry-specification/pull/4802))
 - Declarative configuration: clarify Registry ComponentProvider `type` parameter
   ([#4799](https://github.com/open-telemetry/opentelemetry-specification/pull/4799))
+- Declarative configuration: Update instrumentation config behavior to return
+  empty object when not set
+  ([#4817](https://github.com/open-telemetry/opentelemetry-specification/pull/4817))
 
 ### Common
 

specification/configuration/api.md

@@ -60,9 +60,8 @@ Obtain configuration relevant to instrumentation libraries.
 the [`.instrumentation`](https://github.com/open-telemetry/opentelemetry-configuration/blob/670901762dd5cce1eecee423b8660e69f71ef4be/examples/kitchen-sink.yaml#L438-L439)
 configuration mapping node.
 
-If the `.instrumentation` node is not set, get instrumentation config MUST
-return nil, null, undefined or another language-specific idiomatic pattern
-denoting empty.
+If the `.instrumentation` node is not set, get instrumentation config SHOULD
+return empty object (as if `.instrumentation: {}` was set).
 
 ### ConfigProperties