make oauth endpoints openid compliant

src/Repository/OAuthTokenRepository.php

@@ -28,6 +28,14 @@ class OAuthTokenRepository
         return $this->pdm->selectFromDb($select, OAuthToken::class);
     }
 
+    public function getByAccessToken(string $accessToken): ?OAuthToken
+    {
+        $select = new Select(\Container::$dbConnection);
+        $select->where('access_token', '=', $accessToken);
+
+        return $this->pdm->selectFromDb($select, OAuthToken::class);
+    }
+
     public function getAllExpired(): Generator
     {
         $select = new Select(\Container::$dbConnection);