optimise default getBlockByNumber - skip processing requests of tx bodies

src/main/kotlin/io/emeraldpay/dshackle/upstream/ethereum/LocalCallRouter.kt

@@ -136,6 +136,11 @@ class LocalCallRouter(
             throw RpcException(RpcResponseError.CODE_INVALID_METHOD_PARAMS, "Must provide 2 parameters")
         }
         val number: Long
+        val withTx = params[1].toString().toBoolean()
+        if (withTx) {
+            // with Tx request much more efficient in remote call
+            return null
+        }
         try {
             val blockRef = params[0].toString()
             when {
@@ -165,16 +170,8 @@ class LocalCallRouter(
         } catch (e: IllegalArgumentException) {
             throw RpcException(RpcResponseError.CODE_INVALID_METHOD_PARAMS, "[0] must be a block number")
         }
-        val withTx = params[1].toString().toBoolean()
-        var block = reader.blocksByHeightAsCont()
-            .read(number)
-        block = if (withTx) {
-            block.flatMap {
-                fullBlocksReader.read(it.hash)
-            }
-        } else {
-            block
-        }
-        return block.map { it.json!! }
+
+        return reader.blocksByHeightAsCont()
+            .read(number).map { it.json!! }
     }
 }