Remove duplicated CentOS 7 mirrorlist update logic

Remove duplicated CentOS 7 mirrorlist handling introduced in this commit 52c79b4

Author: 7006

src/common-utils/main.sh

@@ -378,14 +378,6 @@ if [ "${ADJUSTED_ID}" = "rhel" ] && [ "${VERSION_CODENAME-}" = "centos7" ]; then
     sed -i s/^mirrorlist=http/#mirrorlist=http/g /etc/yum.repos.d/*.repo
 fi
 
-if [ "${ADJUSTED_ID}" = "rhel" ] && [ "${VERSION_CODENAME-}" = "centos7" ]; then
-    # As of 1 July 2024, mirrorlist.centos.org no longer exists.
-    # Update the repo files to reference vault.centos.org.
-    sed -i s/mirror.centos.org/vault.centos.org/g /etc/yum.repos.d/*.repo
-    sed -i s/^#.*baseurl=http/baseurl=http/g /etc/yum.repos.d/*.repo
-    sed -i s/^mirrorlist=http/#mirrorlist=http/g /etc/yum.repos.d/*.repo
-fi
-
 # Install packages for appropriate OS
 case "${ADJUSTED_ID}" in
     "debian")