Configurable rate rounding (#5734)

* added invoice hydration of the issuer object
* added "rate calculator" mode
* new config to select rounding mode
* replace static calls with dependency injection

tests/Mocks/RateServiceFactory.php

@@ -0,0 +1,27 @@
+<?php
+
+/*
+ * This file is part of the Kimai time-tracking app.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace App\Tests\Mocks;
+
+use App\Repository\TimesheetRepository;
+use App\Timesheet\RateCalculator\ClassicRateCalculator;
+use App\Timesheet\RateService;
+
+class RateServiceFactory extends AbstractMockFactory
+{
+    public function create(array $rules = [], array $rates = []): RateService
+    {
+        $mock = $this->createMock(TimesheetRepository::class);
+        if (!empty($rates)) {
+            $mock->expects($this->getTestCase()->any())->method('findMatchingRates')->willReturn($rates);
+        }
+
+        return new RateService($rules, $mock, new ClassicRateCalculator());
+    }
+}