Fixes the order of fields of History Response protobuf (#676)

* shifts history response field numbers by 1

* adds changelog

* minor rewording

* minor

CHANGELOG.md

@@ -11,6 +11,8 @@ This release contains the following:
 - Updates the `resume` Nim API to fetch historical messages in sequence of pages.
 - Support for stable version of `relay` protocol, with protocol ID `/vac/waku/relay/2.0.0`
 - Support for multiple protocol IDs - now matches any protocol that adds postfix to stable ID.
+- Updates the order of fields of `HistoryResponse` protobuf message. 
+  The filed numbers of the `HistoryResponse` are shifted up by one to match up the [13/WAKU2-STORE](https://rfc.vac.dev/spec/13/) specs. 
 
 #### General refactoring
 #### Docs

waku/v2/protocol/waku_store/waku_store.nim

@@ -174,17 +174,17 @@ proc init*(T: type HistoryResponse, buffer: seq[byte]): ProtoResult[T] =
   let pb = initProtoBuffer(buffer)
 
   var messages: seq[seq[byte]]
-  discard ? pb.getRepeatedField(1, messages)
+  discard ? pb.getRepeatedField(2, messages)
 
   for buf in messages:
     msg.messages.add(? WakuMessage.init(buf))
 
   var pagingInfoBuffer: seq[byte]
-  discard ? pb.getField(2,pagingInfoBuffer)
+  discard ? pb.getField(3, pagingInfoBuffer)
   msg.pagingInfo= ? PagingInfo.init(pagingInfoBuffer)
 
   var error: uint32
-  discard ? pb.getField(3, error)
+  discard ? pb.getField(4, error)
   msg.error = HistoryResponseError(error)
 
   return ok(msg)
@@ -232,11 +232,11 @@ proc encode*(response: HistoryResponse): ProtoBuffer =
   var output = initProtoBuffer()
 
   for msg in response.messages:
-    output.write(1, msg.encode())
+    output.write(2, msg.encode())
 
-  output.write(2, response.pagingInfo.encode())
+  output.write(3, response.pagingInfo.encode())
 
-  output.write(3, uint32(ord(response.error)))
+  output.write(4, uint32(ord(response.error)))
 
   return output