When building in AOT mode, the BinderChildContextInitializer is unable to get access
to a SpEL expression conversion service in order to properly bind spring.cloud.stream
prefixed properties with values containing SpEL expressions such as headers[partition-key-expression].
However, we don't need to bind at this level of generality (spring.cloud.stream.*) in the
BinderChildContextInitializer since we are only looking for the user defined binders there.
To fix the issue, this commit explicitly binds only the spring.cloud.stream.binders.* properties
and ignores any other binding properties via spring.cloud.stream prefix. Any such conversions
will be done in later phases after the binder contexts are created.
Resolves https://github.com/spring-cloud/spring-cloud-stream/issues/2799
1a62bc3913