Add newline at end of main.cpp

Added a newline at the end of the file to adhere to coding standards.

Author: Fuad-HH

examples/external-usage-example/main.cpp

@@ -6,4 +6,4 @@ int main()
   std::cout << "Testing PCMS dependency export..." << std::endl;
   pcms::printInfo("Dependency test successful!\n");
   return 0;
-}
+}