t1300: add a few more hairy examples of sections becoming empty
During the review of the first iteration of the patch series to remove
sections that become empty upon --unset or --unset-all, Jeff King
identified a couple of problematic cases with the backtracking approach
that was still used then to "look backwards for the section header":
https://public-inbox.org/git/
20180329213229.GG2939@sigill.intra.peff.net/
This patch adds a couple of concocted examples designed to fool a
backtracking parser.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>