problem: returns processed json for block with tx, instead of original json

rel: #45

testing/simple-upstream/src/main/resources/block-0x100001.json

@@ -21,5 +21,6 @@
     "0xe589a39acea3091b584b650158d08b159aa07e97b8e8cddb8f81cb606e13382e"
   ],
   "transactionsRoot": "0xc90078e2af52aef81815cb2a71c22ebd781dd658dd953d9df57f7769a0b2fe51",
-  "uncles": []
+  "uncles": [],
+  "testFoo": "bar"
 }

testing/trial/src/test/groovy/io/emeraldpay/dshackle/testing/trial/proxy/StandardCallsSpec.groovy

@@ -48,4 +48,26 @@ class StandardCallsSpec extends Specification {
         }
         act.error == null
     }
+
+    def "returns original block json"() {
+        when:
+        def act = client.execute("eth_getBlockByNumber", ["0x100001", false])
+        then:
+        act.result != null
+        with(act.result) {
+            testFoo == "bar"
+        }
+        act.error == null
+    }
+
+    def "returns original block json with tx"() {
+        when:
+        def act = client.execute("eth_getBlockByNumber", ["0x100001", true])
+        then:
+        act.result != null
+        with(act.result) {
+            testFoo == "bar"
+        }
+        act.error == null
+    }
 }