t0613: mark as leak-free

t0613: mark as leak-free

We can mark t0613 as leak-free:

    $ make test SANITIZE=leak GIT_TEST_PASSING_SANITIZE_LEAK=check GIT_TEST_SANITIZE_LEAK_LOG=true T=t0613-reftable-write-options.sh
    [...]
    *** t0613-reftable-write-options.sh ***
    in GIT_TEST_PASSING_SANITIZE_LEAK=check mode, setting --invert-exit-code for TEST_PASSES_SANITIZE_LEAK != true
    ok 1 - default write options
    ok 2 - disabled reflog writes no log blocks
    ok 3 - many refs results in multiple blocks
    ok 4 - tiny block size leads to error
    ok 5 - small block size leads to multiple ref blocks
    ok 6 - small block size fails with large reflog message
    ok 7 - block size exceeding maximum supported size
    ok 8 - restart interval at every single record
    ok 9 - restart interval exceeding maximum supported interval
    ok 10 - object index gets written by default with ref index
    ok 11 - object index can be disabled
    # passed all 11 test(s)
    1..11
    # faking up non-zero exit with --invert-exit-code
    make[2]: *** [Makefile:75: t0613-reftable-write-options.sh] Error 1

Do it.

Signed-off-by: Rubén Justo <rjusto@gmail.com>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>