fixup! Make get_array return nil for long strings

Author: romainbrenguier

regression/jbmc-strings/long_string/test_abort.desc

@@ -1,9 +1,10 @@
 CORE
 Test.class
---refine-strings --function Test.checkAbort
-^EXIT=6$
+--refine-strings --function Test.checkAbort --trace
+^EXIT=10$
 ^SIGNAL=0$
+dynamic_object[0-9]*=\(assignment removed\)
 --
 --
-This tests should abort, because concretizing a string of the required
-length may take to much memory.
+This tests that the object does not appear in the trace, because concretizing
+a string of the required length may take to much memory.