postIncludeForBLSStream.py: Fix comment describing the file.

Former-commit-id: 8a61f750a7b1848db424aaa9a365baf6d1dc5f47

Reconstruction/RecExample/RecExCommon/share/postIncludeForBLSStream.py

-#This is a preInclude file to be used to run the BLS stream in production.                                                                                                          
+#This is a postInclude file to be used to run the BLS stream in production.                                                                                                          
 #Author: James Walder   
 removed_items = []