tests: generalize update_valid_1_cert.bash

1. Rename to `update_valid_ee_certs.bash`
2. Don't hardcode location of `bash` for shebang.
3. Remove echo's about potential future extensions.
4. Add a helper function for fetching EE certs.
5. Use helper to update all three valid realworld testcase EE certs
   instead of just `1password_com_valid_1.crt`

src/tests/verification_real_world/update_valid_ee_certs.bash

@@ -0,0 +1,21 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
+
+fetch_ee_cert() {
+  local domain="$1"
+  local out_file="$2"
+
+  echo -n |
+    openssl s_client \
+      -connect "$domain:443" \
+      -servername "$domain" |
+    openssl x509 \
+      -outform DER > "$DIR/$out_file"
+}
+
+fetch_ee_cert "my.1password.com" "1password_com_valid_1.crt"
+fetch_ee_cert "agilebits.com" "agilebits_com_valid_1.crt"
+fetch_ee_cert "lencr.org" "letsencrypt_org_valid_1.crt"