code: public void setSettingsRef(String settingsRef) {
                  if (GitTaskUtils.isNullOrBlankString(settingsRef)) {
                          throw new BuildException("Can't set blank git settings reference.");
                  }
  
                  // no override
                  if (this.settingsRef == null) {
                          this.settingsRef = settingsRef;
                  }
          }
docs: Sets a git settings reference
  
  @antdoc.notrequired
  @param settingsRef the settingsRef to set