Cleanup Dockerfile builds

Add `-y` options to yum clean all
Only delete below /var/cache/dnf so that I can use the
-v /var/cache/dnf:/var/cache/dnf:O option when building
to speed up builds.

Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>

contrib/skopeoimage/stable/Dockerfile

@@ -13,7 +13,7 @@ FROM registry.fedoraproject.org/fedora:32
 # up space.  Also reinstall shadow-utils as without
 # doing so, the setuid/setgid bits on newuidmap
 # and newgidmap are lost in the Fedora images. 
-RUN useradd skopeo; yum -y update; yum -y reinstall shadow-utils; yum -y install skopeo fuse-overlayfs --exclude container-selinux; yum clean all; rm -rf /var/cache /var/log/dnf* /var/log/yum.*;
+RUN useradd skopeo; yum -y update; yum -y reinstall shadow-utils; yum -y install skopeo fuse-overlayfs --exclude container-selinux; yum -y clean all; rm -rf /var/cache/dnf/* /var/log/dnf* /var/log/yum*
 
 # Adjust storage.conf to enable Fuse storage.
 RUN sed -i -e 's|^#mount_program|mount_program|g' -e '/additionalimage.*/a "/var/lib/shared",' -e 's|^mountopt[[:space:]]*=.*$|mountopt = "nodev,fsync=0"|g' /etc/containers/storage.conf

contrib/skopeoimage/testing/Dockerfile

@@ -14,7 +14,7 @@ FROM registry.fedoraproject.org/fedora:32
 # up space.  Also reinstall shadow-utils as without
 # doing so, the setuid/setgid bits on newuidmap
 # and newgidmap are lost in the Fedora images. 
-RUN useradd skopeo; yum -y update; yum -y reinstall shadow-utils; yum -y install skopeo fuse-overlayfs --enablerepo updates-testing --exclude container-selinux; yum clean all; rm -rf /var/cache /var/log/dnf* /var/log/yum.*;
+RUN useradd skopeo; yum -y update; yum -y reinstall shadow-utils; yum -y install skopeo fuse-overlayfs --enablerepo updates-testing --exclude container-selinux; yum -y clean all; rm -rf /var/cache/dnf/* /var/log/dnf* /var/log/yum*
 
 # Adjust storage.conf to enable Fuse storage.
 RUN sed -i -e 's|^#mount_program|mount_program|g' -e '/additionalimage.*/a "/var/lib/shared",' -e 's|^mountopt[[:space:]]*=.*$|mountopt = "nodev,fsync=0"|g' /etc/containers/storage.conf

contrib/skopeoimage/upstream/Dockerfile

@@ -33,7 +33,8 @@ make binary-local;\
 make install;\
 rm -rf /root/skopeo/*; \
 yum -y remove git golang go-md2man make; \
-yum clean all; rm -rf /var/cache /var/log/dnf* /var/log/yum.*;
+yum -y clean all; yum -y clean all; rm -rf /var/cache/dnf/* /var/log/dnf* /var/log/yum*
+
 
 # Adjust storage.conf to enable Fuse storage.
 RUN sed -i -e 's|^#mount_program|mount_program|g' -e '/additionalimage.*/a "/var/lib/shared",' -e 's|^mountopt[[:space:]]*=.*$|mountopt = "nodev,fsync=0"|g' /etc/containers/storage.conf