Change: Reduce RHEL image size by calling "yum clean all" after installing packages.

[cfi-gb]

What

yum clean all was only called before the installation of additional packages and only in the case if UPDATED=true was used.

Before this change:

$ docker image ls rhel:8.7
REPOSITORY   TAG       IMAGE ID       CREATED          SIZE
rhel         8.7       4cc316416a53   11 seconds ago   234MB

after this change:

$ docker image ls rhel:8.7
REPOSITORY   TAG       IMAGE ID       CREATED         SIZE
rhel         8.7       ade26e58d71d   7 seconds ago   225MB

Why

Reduce image size (not much but still worth a minor change like this)

References

None

Checklist

• Tests