Remove hard-coded full pathnames from test

tests/fatal_error_rethrow.phpt

@@ -27,6 +27,6 @@ Fatal error: Uncaught Error: Call to a member function bar() on %s in %s%efatal_
 Stack trace:
 #0 [internal function]: {closure}()
 #1 [internal function]: Closure->__invoke()
-#2 /home/stesie/Projekte/v8js-php7/tests/fatal_error_rethrow.php(16): V8Js->executeString('\nPHP.foo();\n')
+#2 %s%efatal_error_rethrow.php(16): V8Js->executeString('\nPHP.foo();\n')
 #3 {main}
-  thrown in /home/stesie/Projekte/v8js-php7/tests/fatal_error_rethrow.php on line 7
+  thrown in %s%efatal_error_rethrow.php on line 7