t/t5304-prune.sh: prepare for `gc --cruft` by default
Many of the tests in t5304 run `git gc`, and rely on its behavior that
unreachable-but-recent objects are written out loose. This is sensible,
since t5304 deals specifically with this kind of pruning.
If left unattended, however, this test would break when the default
behavior of a bare "git gc" is adjusted to generate a cruft pack by
default.
Ensure that these tests continue to work as-is (and continue to provide
coverage of loose object pruning) by passing `--no-cruft` explicitly.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>