remove double application of text speedup

script dumped from 4.15 already has speed parameters adjusted

this makes it so more of these parameters actually have some visible
effect ingame instead of almost every value going to zero

script/scriptinsert.py

@@ -105,7 +105,7 @@ def adjust_speed(self, origdata):
         #speed (characters per frame) is time divided by length
         #Rounds down. You could try rounding nearest.
         #I found rounding down gives a better experience. YMMV.
-        new_speed = int(orig_time / new_len) - 1
+        new_speed = int(orig_time / new_len)
         if new_speed < 0:   #0 is the fastest it can go (1 character per frame)
             new_speed = 0