Model Builder: Shouldn't complain about missing process if namespace is URL

[m-mohr]

A process graphs with a process that has a URL as namespace is always declaring the node with the URL namespace to be missing. This shouldn't be the case. Simply never complain about a missing process if the namespace is a URL.

{
  "process_graph": {
    "EVI": {
      "process_id": "EVI",
      "arguments": {
        "date": [
          "2022-03-08T00:00:00Z",
          "2022-03-09T00:00:00Z"
        ],
        "polygon": {
          "type": "Polygon",
          "coordinates": [
            [
              [
                5.133324409516575,
                51.17051559917516
              ],
              [
                4.957798897981888,
                51.17051559917516
              ],
              [
                4.957798897981888,
                51.21961284959741
              ],
              [
                5.133324409516575,
                51.21961284959741
              ],
              [
                5.133324409516575,
                51.17051559917516
              ]
            ]
          ]
        }
      },
      "namespace": "[https://openeo.vito.be/openeo/1.1/processes/u:dfa678cb9ab17f65d4f025e30fac5e0d90116176e44fd17d703419322747cbbd%40egi.eu/EVI"](https://openeo.vito.be/openeo/1.1/processes/u:dfa678cb9ab17f65d4f025e30fac5e0d90116176e44fd17d703419322747cbbd%40egi.eu/EVI%22),
      "result": true
    }
  },
  "parameters": []
}