Add `libcore.libcore.internal` tests to the ART Libcore test suite.

Tests execution time: 4.93s on host, 6.80s on device (Pixel XL).

Test: Run Libcore tests on host and target
Change-Id: I5a6d7af9b6823e7ac69834de981d0d65669d8147
diff --git a/tools/run-libcore-tests.sh b/tools/run-libcore-tests.sh
index a12830b..66d5dbd 100755
--- a/tools/run-libcore-tests.sh
+++ b/tools/run-libcore-tests.sh
@@ -95,6 +95,7 @@
                   "libcore.javax.security"
                   "libcore.javax.sql"
                   "libcore.javax.xml"
+                  "libcore.libcore.internal"
                   "libcore.libcore.io"
                   "libcore.libcore.net"
                   "libcore.libcore.reflect"