resolve start space problem in srt

Former-commit-id: 75087aaf862971821be4ce5f63fefb2856884d54

SRT.py

@@ -26,7 +26,7 @@ class SRT_segment(object):
                 self.end_time_str = str(0)+str(self.end_time).split('.')[0]+',000'
             else:
                 self.end_time_str = str(0)+str(self.end_time).split('.')[0]+','+str(self.end_time).split('.')[1][:3]
-            self.source_text = segment['text']
+            self.source_text = segment['text'].lstrip()
             self.duration = f"{self.start_time_str} --> {self.end_time_str}"
             self.translation = ""