NEW: support to config ftp_folder for printer [P1P]

Change-Id: I6a3b2a67d2950e2c1c5267bb7c65d5594924caec
Signed-off-by: Stone Li <stone.li@bambulab.com>
(cherry picked from commit 176e505bcf5f48971302d9aff14e74b118eeafbe)

src/slic3r/GUI/Jobs/PrintJob.hpp

@@ -42,6 +42,7 @@ public:
 
     std::string m_project_name;
     std::string m_dev_ip;
+    std::string m_ftp_folder;
     bool        m_local_use_ssl { true };
     std::string m_access_code;
     std::string task_bed_type;