t0020-crlf: check the right file

t0020-crlf: check the right file

In the test 'checkout with autocrlf=input' in 't0020-crlf.sh', one of
the 'has_cr' checks looks at the non-existing file 'two' instead of
'dir/two'.  The test still succeeds, without actually checking what it
was supposed to, because this check is expected to fail anyway.

As a minimal fix, fix the name of the file to be checked.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>