Add example where the solver potentially runing out of memory

Author: romainbrenguier

regression/strings-smoke-tests/java_int_to_string/test2_bug.desc

@@ -0,0 +1,11 @@
+KNOWNBUG
+Test2.class
+--refine-strings
+^EXIT=10$
+^SIGNAL=0$
+assertion.* line 7 .* SUCCESS$
+assertion.* line 10 .* FAILURE$
+--
+--
+When string-max-length is not set, the solver can run out of memory in
+an unpredictable way.