title: JwtBearerHandler with authorization header for discovery endpoint
body: <p>I'm using ASP.NET Core 2.1 with the JwtBearer scheme for authentication, like so:</p>
  
  <pre><code>public void ConfigureServices(IServiceCollection services)
  {
      services.AddAuthentication(JwtBearerDefaults.AuthenticationScheme)
          .AddJwtBearer(o =&gt;
          {
              // my options here
          });
  }
  </code></pre>
  
  <p>Pretty standard, however the hitch I've run into is my token authorities discovery endpoint requires authorization to access. What I need to do is inject a basic authentication header into the request the JWT middleware does to my authorities endpoint. I'm looking at the configuration options and I'm not seeing anything that allows me to do that. I'm also looking through the source code to see if I can see where the http request is being made but it's pretty obfuscated through abstraction and extension methods and I haven't found it yet.</p>
  
  <p>Would anyone be able to tell me if it is possible to set this somewhere or will I have to create my own authorization handler and tie things together manually? Any advice is appreciated.</p>