Making message mode 'skip-output' the default

The output proxy is not yet supporting forwarding of neither message pairs
nor sequences, this needs to be investigated. Looks like not all parts are
forwarded. The output proxy is based on message forwarding in the core
framework DataProcessingDevice

[480102:checker]: [08:58:09][ERROR] inconsistent number of inputs extracted
[480102:checker]: [08:58:09][ERROR] inconsistent number of inputs extracted
[480102:checker]: [08:58:09][ERROR] Header is not a DataHeader?
[480102:checker]: [08:58:09][INFO] 1 input slots(s), data 0, parts 6, mode 1
[480102:checker]: [08:58:09][FATAL] Test condition "data == *counter" failed

Author: matthiasrichter

Framework/Core/test/test_ExternalFairMQDeviceWorkflow.cxx

@@ -72,7 +72,7 @@ void customize(std::vector<ConfigParamSpec>& workflowOptions)
       "number-of-events,n", VariantType::Int, 10, {"number of events to process"}});
   workflowOptions.push_back(
     ConfigParamSpec{
-      "proxy-mode", VariantType::String, "all", {"proxy mode: all, skip-output, only-output, skip-all"}});
+      "proxy-mode", VariantType::String, "skip-output", {"proxy mode: all, skip-output, only-output, skip-all"}});
 }
 
 #include "Framework/runDataProcessing.h"