hostbuilder add environment variables
var builder = new HostBuilder();
builder
.ConfigureHostConfiguration(config =>
{
config.AddEnvironmentVariables(prefix:"DOTNETCORE_");
})
.ConfigureAppConfiguration((context, config) =>
{
config.AddJsonFile("appsettings.json", optional: false);
config.AddJsonFile($"appsettings.{context.HostingEnvironment.EnvironmentName}.json", optional: true);
})