Add unit tests for existing S3PostUploadSignedPolicy class and fix exception message (#3897)

* add unit tests

update unit tests to add more policies

* fix exception message

* add dev config

* update header

* Update d71acec0-6d1a-4725-bbe6-3191c988be31.json

Author: GarrettBeatty

generator/.DevConfigs/d71acec0-6d1a-4725-bbe6-3191c988be31.json

@@ -0,0 +1,11 @@
+{
+  "services": [
+    {
+      "serviceName": "S3",
+      "type": "patch",
+      "changeLogMessages": [
+        "Fix GetSignedPolicyFromJson error handling exception message"
+      ]
+    }
+  ]
+}

sdk/src/Services/S3/Custom/Util/_bcl/S3PostUploadSignedPolicy.cs

@@ -221,11 +221,11 @@ public static S3PostUploadSignedPolicy GetSignedPolicyFromJson(string policyJson
 
                     // Check if required fields exist and are of the correct type
                     if (!json.TryGetProperty(KEY_POLICY, out var policyNode) || policyNode.ValueKind != JsonValueKind.String)
-                        throw new ArgumentException(string.Format(CultureInfo.InvariantCulture, "JSON document requires '{0}' field"), KEY_POLICY);
+                        throw new ArgumentException(string.Format(CultureInfo.InvariantCulture, "JSON document requires '{0}' field", KEY_POLICY), KEY_POLICY);
                     if (!json.TryGetProperty(KEY_SIGNATURE, out var signatureNode) || signatureNode.ValueKind != JsonValueKind.String)
-                        throw new ArgumentException(string.Format(CultureInfo.InvariantCulture, "JSON document requires '{0}' field"), KEY_SIGNATURE);
+                        throw new ArgumentException(string.Format(CultureInfo.InvariantCulture, "JSON document requires '{0}' field", KEY_SIGNATURE), KEY_SIGNATURE);
                     if (!json.TryGetProperty(KEY_ACCESSKEY, out var accessKeyNode) || accessKeyNode.ValueKind != JsonValueKind.String)
-                        throw new ArgumentException(string.Format(CultureInfo.InvariantCulture, "JSON document requires '{0}' field"), KEY_ACCESSKEY);
+                        throw new ArgumentException(string.Format(CultureInfo.InvariantCulture, "JSON document requires '{0}' field", KEY_ACCESSKEY), KEY_ACCESSKEY);
 
                     return new S3PostUploadSignedPolicy
                     {