Extract confusing multi-line WAYF remember-choice conditions in SingleSignOn

# If applied, this commit will...
Extract two multi-line boolean conditions in SingleSignOn into named
local variables.

# Why is this change needed?
Prior to this change, both conditions mixed a multi-line function call
or comparison with trailing || continuation lines indented deeper than
the if(, which was flagged in review as hard to read ('broken indent?'
and 'rewrite to human readable ifs').

# How does it address the issue?
This change assigns each condition to a clearly named boolean
($legacyRememberChoiceAllowed, $notEligibleForRememberedIdp) before
the if statement, with no change in behavior.

# Provide links to any relevant tickets, articles or other resources
#2091

Author: kayjoosten

library/EngineBlock/Corto/Module/Service/SingleSignOn.php

@@ -230,10 +230,12 @@ public function serve($serviceName, Request $httpRequest)
 
         // Auto-select IdP when 'wayf.rememberChoice' feature is enabled and is allowed for the current request,
         // and the per-SP remembered-choice feature is not enabled.
-        if ($container->getRememberChoice() === true
+        $legacyRememberChoiceAllowed = $container->getRememberChoice() === true
             && $runtime->isRememberChoicePerIdpEnabled() === false
-            && !($request->getForceAuthn() || $request->isDebugRequest())
-        ) {
+            && !$request->getForceAuthn()
+            && !$request->isDebugRequest();
+
+        if ($legacyRememberChoiceAllowed) {
             $cookies = $container->getSymfonyRequest()->cookies->all();
             if (array_key_exists('rememberchoice', $cookies)) {
                 $remembered = json_decode($cookies['rememberchoice']);
@@ -482,14 +484,13 @@ protected function _sendAuthenticationRequestForRememberedIdpPerServiceProvider(
         $runtime = $application->getDiContainerRuntime();
         $log = $this->_server->getLogger();
 
-        if (!RememberedIdpCookie::isEnabledForServiceProvider(
+        $notEligibleForRememberedIdp = !RememberedIdpCookie::isEnabledForServiceProvider(
             $container->getRememberChoice() === true,
             $runtime->isRememberChoicePerIdpEnabled(),
             $sp
-        )
-            || $request->getForceAuthn()
-            || $request->isDebugRequest()
-        ) {
+        ) || $request->getForceAuthn() || $request->isDebugRequest();
+
+        if ($notEligibleForRememberedIdp) {
             return false;
         }