Add release test script

tests/release/test.sh

@@ -0,0 +1,24 @@
+#!/bin/sh -e
+release_test_dir=$(realpath $(dirname $0))
+release_openssl_privkey="$release_test_dir/fake.pem"
+export RELEASE_OPENSSL_PUBKEY="$release_test_dir/fake.pub"
+
+export GNUPGHOME=$(mktemp -d)
+gpg --import "$release_test_dir/fake.asc"
+export RELEASE_GPG_KEY=$(gpg --fingerprint | sed -n 's/ //g; s/.*fingerprint=\(\)/\1/p')
+
+cd $(mktemp -d)
+git clone --single-branch "$release_test_dir/../.." .
+release_num="0.99.0"
+git checkout -b "candidate-$release_num"
+
+need_sig=true
+yes | tools/release.sh --production $release_num 0.999.0 |
+while read line; do
+    if $need_sig && [ "$line" = "Verification Failure" ]; then
+        openssl dgst -sha256 -sign $release_openssl_privkey -out \
+            releases/le*/letsencrypt-auto-source/letsencrypt-auto.sig \
+            releases/le*/letsencrypt-auto-source/letsencrypt-auto
+        need_sig=false
+    fi
+done