Add DER form of test-ca key in-tree. (#2041)

The PKCS11 proxy requires `test/test-ca.key.pem` in DER form. Rather
than generating it when it doesn't exist in `test/entrypoint.sh` and
adding it to the gitignore we've opted to check it in directly.

test/entrypoint.sh

@@ -34,9 +34,6 @@ rabbitmq-setup -server amqp://boulder-rabbitmq
 # out the signing key doesn't require rebuilding the boulder-tools image. Only
 # convert key to DER once per container.
 wait_tcp_port boulder-hsm 5657
-if [ ! -f test/test-ca.key.der ]; then
-    openssl rsa -in test/test-ca.key -inform pem -out test/test-ca.key.der -outform der
-fi
 PKCS11_PROXY_SOCKET="tcp://boulder-hsm:5657" pkcs11-tool --module=/usr/local/lib/libpkcs11-proxy.so --write-object test/test-ca.key.der --type privkey --label key_label --pin 5678 --login --so-pin 1234
 
 if [[ $# -eq 0 ]]; then