Use a pregenerated dhparam.pem for tests

Letting the LE container generate its 2048 bits dhparam can consume up
to five minutes.

test/setup/dhparam.pem

@@ -0,0 +1,8 @@
+-----BEGIN DH PARAMETERS-----
+MIIBCAKCAQEAzB2nIGzpVq7afJnKBm1X0d64avwOlP2oneiKwxRHdDI/5+6TpH1P
+F8ipodGuZBUMmupoB3D34pu2Qq5boNW983sm18ww9LMz2i/pxhSdB+mYAew+A6h6
+ltQ5pNtyn4NaKw1SDFkqvde3GNPhaWoPDbZDJhpHGblR3w1b/ag+lTLZUvVwcD8L
+jYS9f9YWAC6T7WxAxh4zvu1Z0I1EKde8KYBxrreZNheXpXHqMNyJYZCaY2Hb/4oI
+EL65qZq1GCWezpWMjhk6pOnV5gbvqfhoazCv/4OdRv6RoWOIYBNs9BmGho4AtXqV
+FYLdYDhOvN4aVs9Ir+G8ouwiRnix24+UewIBAg==
+-----END DH PARAMETERS-----

test/setup/setup-nginx-proxy.sh

@@ -39,3 +39,7 @@ case $SETUP in
     exit 1
 
 esac
+
+docker run --name helper --volumes-from $NGINX_CONTAINER_NAME busybox true
+docker cp ${TRAVIS_BUILD_DIR}/test/setup/dhparam.pem helper:/etc/nginx/certs
+docker rm -f helper

test/tests/test-functions.sh

@@ -24,24 +24,6 @@ function run_le_container {
 }
 export -f run_le_container
 
-# Wait for the /etc/nginx/certs/dhparam.pem file to exist in container $1
-function wait_for_dhparam {
-  local name="${1:?}"
-  local i=0
-  sleep 1
-  echo -n "Waiting for the $name container to generate a DH parameters file, this might take a while..."
-  until docker exec "$name" [ -f /etc/nginx/certs/dhparam.pem ]; do
-    if [ $i -gt 600 ]; then
-      echo "DH parameters file was not generated under ten minutes by the $name container, timing out."
-      exit 1
-    fi
-    i=$((i + 5))
-    sleep 5
-  done
-  echo "Done."
-}
-export -f wait_for_dhparam
-
 # Wait for the /etc/nginx/certs/$1/cert.pem file to exist inside container $2
 function wait_for_cert {
   local domain="${1:?}"