configure am/pm time-format as user preference (#2789)

src/API/Model/I18nConfig.php

@@ -18,17 +18,6 @@ use JMS\Serializer\Annotation as Serializer;
  */
 final class I18nConfig
 {
-    /**
-     * Format used for 'begin' and 'end'
-     *
-     * @var string
-     *
-     * @Serializer\Expose()
-     * @Serializer\Groups({"Default"})
-     * @Serializer\Type(name="string")
-     * @phpstan-ignore-next-line
-     */
-    private $formDateTime = '';
     /**
      * Format used for toolbar queries
      *
@@ -114,13 +103,6 @@ final class I18nConfig
         return $this;
     }
 
-    public function setFormDateTime(string $formDateTime): I18nConfig
-    {
-        $this->formDateTime = $formDateTime;
-
-        return $this;
-    }
-
     public function setFormDate(string $formDate): I18nConfig
     {
         $this->formDate = $formDate;