t: refactor tests depending on Perl to print data

t: refactor tests depending on Perl to print data

A bunch of tests rely on Perl to print data in various different ways.
These usages fall into the following categories:

  - Print data conditionally by matching patterns. These usecases can be
    converted to use awk(1) rather easily.

  - Print data repeatedly. These usecases can typically be converted to
    use a combination of `test-tool genzeros` and sed(1).

  - Print data in reverse. These usecases can be converted to use
    awk(1) or `sort -r`.

Refactor the tests accordingly so that we can drop a couple of
PERL_TEST_HELPERS prerequisites.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>