bugfix: default config for mcbm_qa.C

macro/mcbm/mcbm_qa.C

@@ -86,6 +86,11 @@ void mcbm_qa(Int_t nEvents = 0,
   TString recFile  = dataset + ".rec.root";
   TString sinkFile = dataset + ".qa.root";
   TString qaConfig = (config.Length() ? config : srcDir + "/macro/qa/configs/qa_tasks_config_" + setupName + ".yaml");
+  if (gSystem->AccessPathName(qaConfig.Data())) {  // file not found, using default one
+    std::cout << "-I- " << myName << ": the QA configuration file " << qaConfig << " not found, using default one\n";
+    qaConfig = srcDir + "/macro/qa/configs/qa_tasks_config_mcbm.yaml";
+  }
+
   TString benchmarkOut = sinkFile + ".qa.benchmark.root";
   // ------------------------------------------------------------------------