tests: migrate from %error-verbose to %define parse.error verbose

* tests/actions.at, tests/c++.at, tests/conflicts.at,
* tests/cxx-type.at, tests/existing.at, tests/glr-regression.at,
* tests/headers.at, tests/input.at, tests/java.at, tests/javapush.at,
* tests/local.at, tests/regression.at, tests/skeletons.at,
* tests/torture.at:
Here.

tests/conflicts.at

@@ -694,7 +694,7 @@ AT_DATA_GRAMMAR([[input.y]],
   ]AT_YYLEX_DECLARE[
 }
 
-%error-verbose
+%define parse.error verbose
 %nonassoc 'a'
 
 %%