Constant WP_CRON_LOCK_TIMEOUT already defined in /htdocs/wp-config.php

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Configurations in wp-config.php should be placed above the comment near the bottom that reads: That’s all, stop editing! Happy Publishing.

Per Editing wp-config.php

The contents of the wp-config-sample.php file are in a very specific order. The order matters. If you already have a wp-config.php file, rearranging the contents of the file may create errors on your blog.

Here are those lines near the bottom:

/* That's all, stop editing! Happy publishing. */

/** Absolute path to the WordPress directory. */
if ( ! defined( 'ABSPATH' ) ) {
define( 'ABSPATH', dirname( __FILE__ ) . "https://wordpress.stackexchange.com/" );
}

/** Sets up WordPress vars and included files. */
require_once( ABSPATH . 'wp-settings.php' );

I’ve added my own configuration above those lines:

define( 'WP_CRON_LOCK_TIMEOUT', 120   ); 
define( 'AUTOSAVE_INTERVAL',    300   );
define( 'WP_POST_REVISIONS',    5     );
define( 'EMPTY_TRASH_DAYS',     7     );
define( 'WP_AUTO_UPDATE_CORE',  true  );

/* That's all, stop editing! Happy publishing. */

/** Absolute path to the WordPress directory. */
if ( ! defined( 'ABSPATH' ) ) {
define( 'ABSPATH', dirname( __FILE__ ) . "https://wordpress.stackexchange.com/" );
}

/** Sets up WordPress vars and included files. */
require_once( ABSPATH . 'wp-settings.php' );

Add your configuration accordingly and those notices should resolve.