修改环境变量相关bug

OTWebSocket.API/Startup.cs

@@ -132,7 +132,8 @@ namespace OTWebSocket.API
 
             var path = Configuration.GetSection("Swagger:VirtualPath").Value;
             string scheme = "https";
-            if (Environment.GetEnvironmentVariable("ASPNETCORE_ENVIRONMENT").Equals("Development"))
+            var env = Environment.GetEnvironmentVariable("ASPNETCORE_ENVIRONMENT");
+            if (!string.IsNullOrEmpty(env) && env.Equals("Development"))
             {
                 scheme = "http";//本地测试使用http协议
             }