The '\n' newline is transformed into a space (0x20) when building
natively on Windows. And unfortunately g_key_file_load_from_file() does
not like this.
The autotools rule works properly on all platforms according to my
tests.
Note that at first, I thought it was a LF vs. CRLF issue, and tried to
special-case Windows, but I realized it's just that 'echo' command
seemingly transform newlines unexpectedly in its Windows form. I didn't
want to waste too much time experimenting alternative calls, especially
as I have to test through CI (so each test is very costly, time-wise).
Instead I go the alternative way of using a pre-generated conf file.
67f7b76e92