[configuration] Specify YAML schema that configuration files should follow

CHANGELOG.md

@@ -46,6 +46,8 @@ release.
 
 - Clarify environment variable substitution is not recursive
   ([#3913](https://github.com/open-telemetry/opentelemetry-specification/pull/3913))
+- Clarify the schema for YAML configuration files
+  ([#3973](https://github.com/open-telemetry/opentelemetry-specification/pull/3973))
 
 ### Common
 

specification/configuration/file-configuration.md

@@ -60,7 +60,7 @@ Configuration files SHOULD use one the following serialization formats:
 ### YAML file format
 
 [YAML](https://yaml.org/spec/1.2.2/) configuration files SHOULD follow YAML spec
-revision >= 1.2.
+revision >= 1.2 and SHOULD use the [v1.2 YAML core schema](https://yaml.org/spec/1.2.2/#103-core-schema).
 
 YAML configuration files MUST use file extensions `.yaml` or `.yml`.