Allow manual_div_ceil

Until our MSRV reaches 1.73.0, we're gonna need
to keep allowing it.

Author: arik-so

ci/check-lint.sh

@@ -35,6 +35,7 @@ RUSTFLAGS='-D warnings' cargo clippy -- \
 	-A clippy::len_without_is_empty \
 	-A clippy::len_zero \
 	-A clippy::let_and_return \
+	-A clippy::manual_div_ceil \
 	-A clippy::manual_filter \
 	-A clippy::manual_map \
 	-A clippy::manual_memcpy \