Add keyUsage checking for CAs
diff --git a/tests/data_files/test-ca2.ku-ds.crt b/tests/data_files/test-ca2.ku-ds.crt
new file mode 100644
index 0000000..c28e17b
--- /dev/null
+++ b/tests/data_files/test-ca2.ku-ds.crt
@@ -0,0 +1,12 @@
+-----BEGIN CERTIFICATE-----
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+BgNVHQ8EBAMCB4AwCgYIKoZIzj0EAwIDZwAwZAIwGRCmU/rWNjW13g8ITuq3pMXb
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+nQdac59ev+lH+ju6wET3jNDjUthUPrdgqa54+UWQ5r4=
+-----END CERTIFICATE-----