Drop update-packages.sh from Dockerfile

* manylinux_2_28 base image is AlmaLinux, and prelink is not present in
  repositories
* older base images have archived their repositories, making it hard to
  install prelink
* The build runs without prelink available

build-scripts/manylinux-container-image/Dockerfile

@@ -5,9 +5,6 @@ ARG LIBSSH_VERSION=0.9.6
 MAINTAINER Python Cryptographic Authority
 WORKDIR /root
 
-ADD update-packages.sh /root/update-packages.sh
-RUN ./update-packages.sh
-
 ADD build_utils.sh /root/build_utils.sh
 ADD install_perl.sh /root/install_perl.sh
 RUN ./install_perl.sh "${RELEASE}"