Replace DocumentTemplate with ModuleTemplate

[SSFGizmo]

(1/1) Error
Class "TYPO3\CMS\Backend\Template\DocumentTemplate" not found

• https://docs.typo3.org/c/typo3/cms-core/master/en-us/Changelog/10.3/Deprecation-90421-DocumentTemplate.html?highlight=documenttemplate

• https://docs.typo3.org/m/typo3/reference-coreapi/master/en-us/ApiOverview/BackendModules/TemplateClass/BackendTemplateViewWithoutExtbase.html

• https://api.typo3.org/master/class_t_y_p_o3_1_1_c_m_s_1_1_backend_1_1_template_1_1_module_template.html