Add test for limit on intermediate certificates

Inspired by test code provided by Nicholas Wilson in PR #351.

The test will fail if someone sets MAX_INTERMEDIATE_CA to a value larger than
18 (default is 8), which is hopefully unlikely and can easily be fixed by
running long.sh again with a larger value if it ever happens.

Current behaviour is suboptimal as flags are not set, but currently the goal
is only to document/test existing behaviour.
diff --git a/tests/data_files/dir-maxpath/06.crt b/tests/data_files/dir-maxpath/06.crt
new file mode 100644
index 0000000..36f99d2
--- /dev/null
+++ b/tests/data_files/dir-maxpath/06.crt
@@ -0,0 +1,12 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----