Remove T+=1 from for loop (used to be while loop)

Spotted by @ankeshanand

Author: Kaixhin

main.py

@@ -106,7 +106,6 @@ def log(s):
     if args.reward_clip > 0:
       reward = max(min(reward, args.reward_clip), -args.reward_clip)  # Clip rewards
     mem.append(state, action, reward, done)  # Append transition to memory
-    T += 1
 
     # Train and test
     if T >= args.learn_start: