Support specifying submodules in poller and discovery for debug (#8896)

Mostly useful for debugging

DO NOT DELETE THIS TEXT

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includes/discovery/sensors.inc.php

@@ -1,5 +1,6 @@
 <?php
 
+use LibreNMS\Config;
 use LibreNMS\Device\YamlDiscovery;
 use LibreNMS\OS;
 
@@ -58,6 +59,10 @@ $run_sensors = array(
     'eer',
     'waterflow',
 );
+
+// filter submodules
+$run_sensors = array_intersect($run_sensors, Config::get('discovery_submodules.sensors', $run_sensors));
+
 sensors($run_sensors, $device, $valid, $pre_cache);
 unset(
     $pre_cache,