util/lint: Remove the extra `\` in lint-stable-003-whitespace

A following error occurred when I commit, it seems that the extra `\`
after `\.md$` is unnecessary.

File Binary file src/mainboard/google/guybrush/data.apcb matches has
lines ending with whitespace.
File Binary file src/mainboard/google/skyrim/data.apcb matches has
lines ending with whitespace.
File Binary file src/mainboard/google/zork/data.apcb matches has
lines ending with whitespace.
test failed

Signed-off-by: Ruihai Zhou <zhouruihai@huaqin.corp-partner.google.com>
Change-Id: I315a37ccc3c6ebb67f7a250402549761c699dd1b
Reviewed-on: https://review.coreboot.org/c/coreboot/+/79782
Reviewed-by: cong yang <yangcong5@huaqin.corp-partner.google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Yu-Ping Wu <yupingso@google.com>
Reviewed-by: Yidi Lin <yidilin@google.com>

0 files changed, 0 insertions, 0 deletions