issue #10240 Multi-line doc not recognized in Python class field

Improve handling of start of a special comment block.
(Looks like it should not be corrected at other places)

Author: albert-github

src/pyscanner.l

@@ -716,7 +716,7 @@ ID        [a-z_A-Z%]+{IDSYM}*
                         BEGIN(TripleComment);
                       }
 
-    {STARTDOCSYMS}/[^#]  {  // start of a special comment
+    {STARTDOCSYMS}/[^#\n] {  // start of a special comment
                         initSpecialBlock(yyscanner);
                         BEGIN(SpecialComment);
                       }