minor

Change-Id: I2e6b7fd2edff7a04e47d1395d3b120e46ff24bf3
diff --git a/tests/unit-tests/config-files/config-ca-2 b/tests/unit-tests/config-files/config-ca-2
index 9b7c2bd..0c87ec9 100644
--- a/tests/unit-tests/config-files/config-ca-2
+++ b/tests/unit-tests/config-files/config-ca-2
@@ -3,7 +3,6 @@
   "ca-info": "missing max validity period, max suffix length, and probe",
   "supported-challenges":
   [
-      { "challenge": "pin" },
-      { "challenge": "email" }
+      { "challenge": "pin" }
   ]
 }
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