Update CentOS 8 smoke vm's with vault repositories (#5092)

Update CentOS 8 smoke vm's with vault repositories

Problem: CentOS 8 reached its EOL alongside its public mirrors, making
all the smoke test fail at provisioning time.

Solution: Point all the CentOS repositories to vault.

Signed-off-by: Jonnatan Jossemar Cordero <jonnatan.cordero@suse.com>

tests/vagrant/install/centos-8/Vagrantfile

@@ -14,6 +14,14 @@ Vagrant.configure("2") do |config|
 
   config.vm.define 'install-centos-8', primary: true do |test|
     test.vm.hostname = 'smoke'
+    test.vm.provision 'centos8-repos-point2vault', type: 'shell', run: 'once' do |sh|
+      sh.env = { :PATH => '/usr/local/bin:/usr/local/sbin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin' }
+      sh.inline = <<~'SHELL'
+        #!/bin/sh
+        find /etc/yum.repos.d -type f -name '*.repo' -exec \
+          sed -i -e '/mirrorlist.*/d' -e 's%#baseurl=http://mirror.centos.org%baseurl=http://vault.centos.org%g' {} \;
+      SHELL
+    end
     test.vm.provision 'k3s-upload', type: 'file', run: 'always', source: ENV['TEST_INSTALL_SH'], destination: 'install.sh'
     test.vm.provision 'k3s-install', type: 'k3s', run: 'once' do |k3s|
       k3s.installer_url = 'file:///home/vagrant/install.sh'