text: Title: Add support for setting httpx client options
  Body: ## Problem
  
  <!-- A clear and concise description of what the problem is. Ex. I'm always frustrated when [...] -->
  
  While running the `postgresql` integration tests on a slow connection I ran into a lot of `httpx.ReadTimeout` errors.
  
  ## Suggested solution
  
  <!-- A clear and concise description of what you want to happen. -->
  
  We should either increase the timeout option or allow users to set it themselves, maybe something like:
  
  ```py
  client = Client(
      http={
          'timeout': 10,
      },
  )
  ```
  