Updates from code review

Thanks @kukks!

BTCPayServer.Client/BTCPayServerClient.Health.cs

@@ -9,7 +9,7 @@ namespace BTCPayServer.Client
     {
         public virtual async Task<ApiHealthData> GetHealth(CancellationToken token = default)
         {
-            var response = await _httpClient.SendAsync(CreateHttpRequest("api/v1/health", bodyPayload: new {}), token);
+            var response = await _httpClient.SendAsync(CreateHttpRequest("api/v1/health"), token);
             return await HandleResponse<ApiHealthData>(response);
         }
     }

BTCPayServer/Controllers/GreenField/HealthController.cs

@@ -12,7 +12,10 @@ namespace BTCPayServer.Controllers.GreenField
         [HttpGet("~/api/v1/health")]
         public ActionResult GetHealth(NBXplorerDashboard dashBoard)
         {
-            ApiHealthData model = new ApiHealthData() {Synchronized = dashBoard.IsFullySynched()};
+            ApiHealthData model = new ApiHealthData()
+            {
+                Synchronized = dashBoard.IsFullySynched()
+            };
             return Ok(model);
         }
     }

BTCPayServer/wwwroot/swagger/v1/swagger.template.health.json

@@ -32,7 +32,7 @@
                 "properties": {
                     "synchronized": {
                         "type": "boolean",
-                        "description": "True if the instance is fully synchronized"
+                        "description": "True if the instance is fully synchronized, according to NBXplorer"
                     }
                 }
             }