Fix a failing test due to thread stack overflow

--- a/check/chk_fhan4	2018-03-13 15:27:11.000000000 -0300
+++ b/check/chk_fhan4	2022-10-14 18:51:12.604731890 -0300
@@ -1,4 +1,5 @@
 #! /bin/sh
 unset LANG
+export PARI_SIZE=2048000
 ../src/icas TP04-sol.cas > TP04.tst
 diff TP04.tst TP04-sol.cas.out1
