Issue #2290325 by cs_shadow: Get rid of form builder functions topic and references to it

core/includes/form.inc

core/modules/color/color.module

core/modules/editor/editor.admin.inc

...dules/file/tests/file_module_test/file_module_test.module

core/modules/locale/src/Form/ImportForm.php

core/modules/shortcut/shortcut.admin.inc

core/modules/system/src/Form/ThemeAdminForm.php

core/modules/system/tests/modules/form_test/form_test.module

core/modules/update/update.manager.inc