Tweak debug logging

lib/Backend/UserBackend.php

@@ -345,9 +345,12 @@ final class UserBackend extends ABackend implements
         }
 
         if ($isCorrect !== true) {
-            $this->logger->info(
+            $this->logger->error(
                 "Invalid password attempt for user: $uid",
-                ["app" => $this->appName]
+                [
+					"app" => $this->appName,
+					'exception' => new \Exception('TRACE PROVIDER'),
+				]
             );
             return false;
         }

lib/Cache.php

@@ -61,7 +61,7 @@ class Cache
             $this->cache = $factory->createDistributed();
             $logger->debug("Distributed cache initiated.", ["app" => $AppName]);
         } else {
-            $logger->warning(
+            $logger->debug(
                 "There's no distributed cache available, fallback to null cache.",
                 ["app" => $AppName]
             );