Fix streaming principle image

Signed-off-by: Thomas Sedlmayer <[email protected]>

Author: thomassedlmayer

doc/architecture/architecture_overview.adoc

@@ -40,7 +40,7 @@ The `StreamingUpdate` interface enables partial ground truth updates to modules
 
 [#fig-interface-streaming]
 .Interface for partial ground truth updates
-image::{images_open_simulation_interface}/osi-streaming-principle.png[1100]
+image::{images_open_simulation_interface}/osi-streaming-principle.PNG[1100]
 
 NOTE: OSI uses singular instead of plural for `repeated` field names.