Update check-warnings.py

Author: AA-Turner

Doc/tools/check-warnings.py

@@ -15,7 +15,7 @@
 from typing import TextIO
 
 # Fail if NEWS nit found before this line number
-NEWS_NIT_THRESHOLD = 8550
+NEWS_NIT_THRESHOLD = 7850
 
 # Exclude these whether they're dirty or clean,
 # because they trigger a rebuild of dirty files.