fix: reconcile error handling

[yashmehrotra]

We were getting empty errors as json.Marshal always marshals error type as {} due to it being an interface

To do: Also if summary.Error is non nil, job history returns success since we do not update error count, this needs to be fixed in mission-control

Have fixed this, but UI is now having an issue rendering it

Error details:

{
  "errors": "job_history: failed to push job_history to upstream: upstream server returned error status[500]: Internal Server Error; ",
  "summary": {
    "checks": {
      "success": 25
    },
    "components": {
      "success": 103
    },
    "job_history": {
      "error": "failed to push job_history to upstream: upstream server returned error status[500]: Internal Server Error"
    },
    "config_items": {
      "success": 28
    },
    "check_statuses": {
      "success": 81
    },
    "config_changes": {
      "success": 35
    },
    "config_relationships": {
      "success": 12
    },
    "component_relationships": {
      "success": 3
    },
    "config_component_relationships": {
      "success": 1
    }
  }
}

[adityathebe]

I think we can make ReconcileSummary.Error a string instead of a adding a new type.

[yashmehrotra]

@adityathebe I was thinking about doing that first, but thought we might need to use that error later ?

I'm okay to do it either way

[moshloop]

@adityathebe / @yashmehrotra - I think we should just use the OopsError type which has custom JSON marshaller

[yashmehrotra]

@moshloop Updated to use oops