fix: change default temporary path to a relative one (#326)

In case of installation on Windows, having absolute path "/tmp" as default value causes that CSS, JS files are not generated properly and the theme is not rendered correctly.

Author: alexsenatore

config/sync/system.file.yml

@@ -1,5 +1,5 @@
 allow_insecure_uploads: false
 default_scheme: public
 path:
-  temporary: /tmp
+  temporary: sites/default/files/tmp
 temporary_maximum_age: 21600