fix: added 9 string guitars to gtp import (musescore#25877)

Author: mikekirin

src/importexport/guitarpro/internal/importgtp.cpp

@@ -2853,10 +2853,11 @@ static void createLinkedTabs(MasterScore* score)
                 StaffTypes::TAB_5SIMPLE,
                 StaffTypes::TAB_6SIMPLE,
                 StaffTypes::TAB_7SIMPLE,
-                StaffTypes::TAB_8SIMPLE
+                StaffTypes::TAB_8SIMPLE,
+                StaffTypes::TAB_9SIMPLE,
             };
 
-            size_t index = (lines >= 4 && lines <= 8) ? lines - 4 : 2;
+            size_t index = (lines >= 4 && lines <= 9) ? lines - 4 : 2;
 
             dstStaff->setStaffType(fr, *StaffType::preset(types.at(index)));
             dstStaff->setLines(fr, static_cast<int>(lines));