docs: public static void setPlatform(Platform platform) throws PlatformAlreadyAssignedException {
          // prevent changing the platform once it has been initially set
          if(PlatformManager.platform != null){
              throw new PlatformAlreadyAssignedException(PlatformManager.platform);
          }
  
          // set internal platform instance
          PlatformManager.platform = platform;
  
          // apply Pi4J platform system property
          System.setProperty("pi4j.platform", platform.id());
      }