fix(monitoring): consolidate prerequisite installation

[fruch]

Replaced distro-specific Docker installation code with a unified bash script that properly installs docker-ce, docker-ce-cli, and containerd.io from Docker's official repository.

The new script:

• Uses Docker's official GPG key with modern keyring management
• Properly detects Debian/Ubuntu vs CentOS/RHEL systems
• Dynamically handles PEP 668 --break-system-packages for pip
• Installs docker-compose-plugin as part of the installation
• Removes deprecated apt-key usage in favor of /etc/apt/keyrings

Testing

• 🟢 provision test (failing on other issue during the test, monitoring setup works as expected)
• 🟢 baremetal (test before this PR created, and proven to work on OCI setups)
• 🟢 monitor with centos based install - manager test - https://jenkins.scylladb.com/view/staging/job/scylla-staging/job/fruch/job/manager-rocky9-installation-test/1

PR pre-checks (self review)

• I added the relevant backport labels
• I didn't leave commented-out/debugging code

Reminders

• Add New configuration option and document them (in sdcm/sct_config.py)
• Add unit tests to cover my changes (under unit-test/ folder)
• Update the Readme/doc folder relevant to this change (if needed)

[soyacz]

Isn't this inified way of installation?:

curl -fsSL https://get.docker.com -o get-docker.sh
sudo sh get-docker.sh

I don't see much diff in this PR vs current approach

[fruch]

Isn't this inified way of installation?:

curl -fsSL https://get.docker.com -o get-docker.sh
sudo sh get-docker.sh

I don't see much diff in this PR vs current approach

it doesn't have wait_for_apt_lock,

regardless before this PR there were 4 different code flows on how to install, base on specific versions of distros.

could adapt it to use get-docker.sh, but in the past we moved away for all bunch of reasons (which I don't remember)