PHP 8.5 | Tests: prevent deprecation notice for Reflection*::setAccessible()

Since PHP 8.1, calling the `Reflection*::setAccessible()` methods is no longer necessary as reflected properties/methods/etc will always be accessible.
However, the method calls are still needed for PHP < 8.1.

As of PHP 8.5, calling the `Reflection*::setAccessible()` methods is now formally deprecated and will yield a deprecation notice, which will fail test runs.
As of PHP 9.0, the `setAccessible()` method(s) will be removed.

With the latter in mind, this commit prevents the deprecation notice by making the calls to `setAccessible()` conditional.

Silencing the deprecation would mean, this would need to be "fixed" again come PHP 9.0, while the current solution should be stable, including for PHP 9.0.

Ref: https://wiki.php.net/rfc/deprecations_php_8_5#extreflection_deprecations

Author: jrfnl

Tests/FeatureComplete/Config/GetHelpTest.php

@@ -130,13 +130,13 @@ public function testGetHelpWithColors()
         $config          = new Config(new TestWriter());
 
         $getHelp = new ReflectionMethod($config, 'getHelp');
-        $getHelp->setAccessible(true);
+        (\PHP_VERSION_ID < 80100) && $getHelp->setAccessible(true);
 
         $actual = $getHelp->invoke($config);
         $actual = \str_replace(["\r\n", "\r"], "\n", $actual);
 
         // Reset to prevent influencing other tests, even if this test would fail.
-        $getHelp->setAccessible(false);
+        (\PHP_VERSION_ID < 80100) && $getHelp->setAccessible(false);
 
         $this->assertSame($this->expectedOutputColorized, $actual);
     }