sparsify
zero free blocks from ext2, ext3 and ext4 file-systems
RUN apt-get update && \
apt-get install -y zerofree
RUN apt-get update && \
apt-get install -y zerofree
RUN apt-get update && \
apt-get install -y zerofree
RUN dnf install -y zerofree
RUN apt-get update && \
apt-get install -y zerofree