phpstan improvements (#3092)

src/Entity/Timesheet.php

@@ -134,7 +134,7 @@ class Timesheet implements EntityWithMetaFields, ExportItemInterface
      */
     private $begin;
     /**
-     * @var DateTime
+     * @var DateTime|null
      *
      * @Serializer\Expose()
      * @Serializer\Groups({"Default"})
@@ -160,7 +160,7 @@ class Timesheet implements EntityWithMetaFields, ExportItemInterface
      */
     private $localized = false;
     /**
-     * @var int
+     * @var int|null
      *
      * @Serializer\Expose()
      * @Serializer\Groups({"Default"})
@@ -202,7 +202,7 @@ class Timesheet implements EntityWithMetaFields, ExportItemInterface
      */
     private $project;
     /**
-     * @var string
+     * @var string|null
      *
      * @Serializer\Expose()
      * @Serializer\Groups({"Default"})
@@ -240,7 +240,7 @@ class Timesheet implements EntityWithMetaFields, ExportItemInterface
      */
     private $fixedRate = null;
     /**
-     * @var float
+     * @var float|null
      *
      * @Serializer\Expose()
      * @Serializer\Groups({"Entity"})