t2000: consolidate second scenario into a single test block
The second test scenario in t2000 consists of several fragmented test_expect_success blocks that handle data setup, tree writes, execution of git-checkout-index, and final state validation. Consolidate these nine separate blocks into a single self-contained test block. This follows the modern Git testing standard where setup, execution, and validation of a single logical scenario are kept together. As a result of this consolidation, the show_files() helper and its associated test_debug calls are no longer used and have been removed. This also removes a dependency on the non-portable 'find -ls' command. Helped-by: Karthik Nayak <karthik.188@gmail.com> Helped-by: Junio C Hamano <gitster@pobox.com> Signed-off-by: Zakariyah Ali <zakariyahali100@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>