Correct caddy PHP_VALUE value as it doesn't support \n

[danny6167]

Line breaks in environment variables in caddy fpm configs don't support the \n notation.

This was causing PHP to set upload_max_filesize to 100M \n post_max_size = 100M.

This lead to upload_max_filesize being evaluated to an invalid value that causes file uploads (such as egg imports) to fail due to the size being above upload_max_filesize.

This PR replaces the \n with an actual newline.

I've confirmed this works in a fresh testing environment.

[VasilisThePikachu]

Just tested this myself and it works correctly

insert github approved

[hexlocation]

+1 had been diagnosing this issue for hours, this fixed it :3