Make cacerts.bks available to the simulator too.

This lets you successfully run more tests on a sim-eng build than otherwise,
by bringing us in line with the normal on-device configuration.
diff --git a/run-core-tests.sh b/run-core-tests.sh
index 0246206..03ba43f 100755
--- a/run-core-tests.sh
+++ b/run-core-tests.sh
@@ -72,6 +72,7 @@
 cd $datadir
 exec $valgrind $exe \
      -Duser.language=en -Duser.region=US -Djava.io.tmpdir=$datadir \
+     -Djavax.net.ssl.trustStore=$base/system/etc/security/cacerts.bks \
      -Xmx512M -Xss32K \
      -Xbootclasspath:$bpath -classpath $cpath $debug_opts \
      com.google.coretests.Main "$@"