Shallow copies are quite common on CI platforms nowadays, making REBOOT
tag unavailable, thus producing following confusing errors in the build
logs:
fatal: Invalid revision range ee53a240ac902dc83209008a2671e7fdcf55957a..HEAD
fatal: Invalid revision range ee53a240ac902dc83209008a2671e7fdcf55957a..0493d57e04774d47921a7d2014b567455d5dc16b
Signed-off-by: Petr Štetiar <ynezz@true.cz>