APC: Add support for Battery Recommended Days Remaining (#14653)

* APC: Add support for Battery Recommended Days Remaining

* Extract number from string later during polling
Odd that this is different from the discovery process

* wip

* wip

* Apply fixes from StyleCI

* wip

* wip

* Apply fixes from StyleCI

---------

Co-authored-by: Tony Murray <[email protected]>

tests/OSModulesTest.php

@@ -88,6 +88,8 @@ class OSModulesTest extends DBTestCase
      */
     public function testOS($os, $variant, $modules)
     {
+        // Lock testing time
+        $this->travelTo(new \DateTime('2022-01-01 00:00:00'));
         $this->requireSnmpsim();  // require snmpsim for tests
         // stub out Eventlog::log and Fping->ping, we don't need to store them for these tests
         $this->stubClasses();
@@ -145,6 +147,7 @@ class OSModulesTest extends DBTestCase
         }
 
         DeviceCache::flush(); // clear cached devices
+        $this->travelBack();
     }
 
     public function dumpedDataProvider()