Add tests for verify_restartable()
For selection of test cases, see comments added in the commit.
It makes the most sense to test with chains using ECC only, so for the chain
of length 2 we use server10 -> int-ca3 -> int-ca2 and trust int-ca2 directly.
Note: server10.crt was created by copying server10_int3_int-ca2.crt and
manually truncating it to remove the intermediates. That base can now be used
to create derived certs (without or with a chain) in a programmatic way.
diff --git a/tests/data_files/server10_int3-bs.pem b/tests/data_files/server10_int3-bs.pem
new file mode 100644
index 0000000..a9e0615
--- /dev/null
+++ b/tests/data_files/server10_int3-bs.pem
@@ -0,0 +1,22 @@
+-----BEGIN CERTIFICATE-----
+MIIBWjCCAQCgAwIBAgIBSzAKBggqhkjOPQQDAjBKMQswCQYDVQQGEwJVSzERMA8G
+A1UEChMIbWJlZCBUTFMxKDAmBgNVBAMTH21iZWQgVExTIFRlc3QgaW50ZXJtZWRp
+YXRlIENBIDMwHhcNMTUwOTAxMTM0NzU1WhcNMjUwODI5MTM0NzU1WjAUMRIwEAYD
+VQQDEwlsb2NhbGhvc3QwWTATBgcqhkjOPQIBBggqhkjOPQMBBwNCAAQcbffp2qXq
+oZyychmoCRxzrd4Vu96m47NPBehtEC46aTeXgDnBdf++znABrAtfXBRNQz8ARIeY
+Bmskr22rlKjyow0wCzAJBgNVHRMEAjAAMAoGCCqGSM49BAMCA0gAMEUCIQDLc+Io
+rg8VxEbCgVv8iH+kOIEn9MjhpvKzvwUoV+6rjQIgZU/RXAyc1a+H2+soGfNEIOBQ
+AzO3pJx7WJAApZuBX1Q=
+-----END CERTIFICATE-----
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----