t0060: preemptively adjust alignment

We are about to adjust t0060 for the new default branch name `main`. This name is two characters shorter and therefore needs two spaces more padding to align correctly. Adjusting the alignment before the big search-and-replace makes it easier to verify that the final result does not leave any misaligned lines behind. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>