Greenfield: Rename API key redirect params; switch to POST body (#1898)

* Rename user param to userId in API key redirect

This way it is clearer what to expect and it also make the parameteer easier to consume.

* Post redirect: Allow form url and prettify page

- Form URL as alternative to controller/action for external URLs
- Making it look nice and add explanation for non-JS case

* APIKeys: Minor view updates

fix

* APIKeys: Use POST redirect for confirmation

fix

* UI: Minor update to confirm view

Tidies it up and adapts to the newly added ConfirmAPIKeys view.

* APIKeys: Update delete view

Structures the information in title and description better.

* APIKeys: Distinguish authorize and confirm (reuse)

* Upgrade ChromeDriver

* Test fixes

* Clean up PostRedirect view

By adding missing forgery token

* Re-add tests for callback post values

* Rename key param to apiKey in API key redirect

* Update BTCPayServer/wwwroot/swagger/v1/swagger.template.authorization.json

Co-authored-by: Andrew Camilleri <evilkukka@gmail.com>

* Use DEBUG conditional for postredirect-callback-test route

* Remove unnecessary ChromeDriver references

* Add debug flag

* Remove debug flags

Co-authored-by: Andrew Camilleri <evilkukka@gmail.com>

BTCPayServer/Controllers/HomeController.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.Diagnostics;
 using System.IO;
 using System.Linq;
@@ -12,6 +13,7 @@ using BTCPayServer.Security;
 using BTCPayServer.Services.Apps;
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Hosting;
+using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Identity;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.Extensions.FileProviders;
@@ -139,7 +141,6 @@ namespace BTCPayServer.Controllers
             return View();
         }
 
-
         [HttpPost]
         [Route("translate")]
         public async Task<IActionResult> BitpayTranslator(BitpayTranslatorViewModel vm)
@@ -199,6 +200,18 @@ namespace BTCPayServer.Controllers
             return View("RecoverySeedBackup", vm);
         }
 
+        [HttpPost]
+        [Route("postredirect-callback-test")]
+        public ActionResult PostRedirectCallbackTestpage(IFormCollection data)
+        {
+            var list = data.Keys.Aggregate(new Dictionary<string, string>(), (res, key) =>
+            {
+                res.Add(key, data[key]);
+                return res;
+            });
+            return Json(list);
+        }
+
         public IActionResult Error()
         {
             return View(new ErrorViewModel { RequestId = Activity.Current?.Id ?? HttpContext.TraceIdentifier });