bpo-42246: Don't forget the entry block when ensuring that all exits have a line number (GH-23636)

Don't forget the entry block when ensuring that all exits have a line number.
diff --git a/Python/importlib.h b/Python/importlib.h
index c5ff9ec..179f8df 100644
--- a/Python/importlib.h
+++ b/Python/importlib.h
@@ -1243,7 +1243,7 @@ const unsigned char _Py_M__importlib_bootstrap[] = {
     114,32,109,111,100,117,108,101,32,99,114,101,97,116,105,111,
     110,46,78,114,10,0,0,0,114,161,0,0,0,114,10,0,
     0,0,114,10,0,0,0,114,11,0,0,0,114,150,0,0,
-    0,66,3,0,0,115,4,0,0,0,4,128,255,128,122,28,
+    0,66,3,0,0,115,4,0,0,0,4,0,255,128,122,28,
     70,114,111,122,101,110,73,109,112,111,114,116,101,114,46,99,
     114,101,97,116,101,95,109,111,100,117,108,101,99,1,0,0,
     0,0,0,0,0,0,0,0,0,3,0,0,0,4,0,0,