Add OAuth URLs to the CapabilityStatement

[qligier]

Fixes #135

{
  "resourceType": "CapabilityStatement",
  "id": "58c3b803-db31-41ce-be2b-7bff6995e74f",
  "name": "RestServer",
  "status": "active",
  "date": "2024-02-29T10:44:50.071+01:00",
  "publisher": "Not provided",
  "kind": "instance",
  "software": {
    "name": "HAPI FHIR Server",
    "version": "6.8.3"
  },
  "implementation": {
    "description": "HAPI FHIR",
    "url": "http://localhost:9090/mag-pmp2/fhir"
  },
  "fhirVersion": "4.0.1",
  "format": [ "application/fhir+xml", "xml", "application/fhir+json", "json", "html/json", "html/xml" ],
  "rest": [ {
    "mode": "server",
    "security": {
      "extension": [ {
        "url": "http://fhir-registry.smarthealthit.org/StructureDefinition/oauth-uris",
        "extension": [ {
          "url": "token",
          "valueString": "https://test.ahdis.ch/mag-pmp2/camel/token"
        }, {
          "url": "authorize",
          "valueString": "https://test.ahdis.ch/mag-pmp2/camel/authorize"
        } ]
      } ]
    },
    "resource": [ {