[HttpClient] Add support for load balancing cookies

[victhorbi]

Context
Some clients might want to use load balancing cookies:

https://vechain.atlassian.net/wiki/spaces/NodeOps/pages/246251522/Node+Usage#Load-Balancing

Idea is to see how we could support that in the SDK
Using this cookie on our own nodes avoids the "Level db not found" error when a client is switching between nodes and get switched to a node not quite in sync.

Axios does automatically add the headers that are in a response in the following request, but we now use Fetch.

Description
Add the possibility to include the header cookies automatically with every request.

Acceptance
The User must select either to use the cookies automatically, or not.

[victhorbi]

Related to #1124