Fixup scripts to set up a new CI node (#9348)

* Clean up node setup scripts for new CI boxes

* Move files under ci directory

* Set CUDA env var to setup cuda drivers

* Fixup and add README

* shellcheck

* Apply review feedback, rename dir and setup files

Co-authored-by: publish-docs.sh <maintainers@solana.com>

ci/setup-new-buildkite-agent/setup-new-machine.sh

@@ -0,0 +1,49 @@
+#!/usr/bin/env bash
+
+HERE="$(dirname "$0")"
+SOLANA_ROOT="$HERE"/../..
+
+# shellcheck source=ci/setup-new-buildkite-agent/utils.sh
+source "$HERE"/utils.sh
+
+ensure_env || exit 1
+
+set -ex
+
+apt update
+apt upgrade -y
+
+cat >/etc/apt/apt.conf.d/99-solana <<'EOF'
+// Set and persist extra caps on iftop binary
+Dpkg::Post-Invoke { "which iftop 2>&1 >/dev/null && setcap cap_net_raw=eip $(which iftop) || true"; };
+EOF
+
+apt install -y build-essential pkg-config clang cmake sysstat linux-tools-common \
+  linux-generic-hwe-18.04-edge linux-tools-generic-hwe-18.04-edge \
+  iftop heaptrack jq ruby python3-venv gcc-multilib libudev-dev
+
+gem install ejson ejson2env
+mkdir -p /opt/ejson/keys
+
+"$SOLANA_ROOT"/net/scripts/install-docker.sh
+usermod -aG docker "$SETUP_USER"
+"$SOLANA_ROOT"/net/scripts/install-certbot.sh
+"$HERE"/setup-sudoers.sh
+"$HERE"/setup-ssh.sh
+
+"$HERE"/disable-nouveau.sh
+"$HERE"/disable-networkd-wait.sh
+
+"$SOLANA_ROOT"/net/scripts/install-earlyoom.sh
+"$SOLANA_ROOT"/net/scripts/install-nodejs.sh
+"$SOLANA_ROOT"/net/scripts/localtime.sh
+"$SOLANA_ROOT"/net/scripts/install-redis.sh
+"$SOLANA_ROOT"/net/scripts/install-rsync.sh
+"$SOLANA_ROOT"/net/scripts/install-libssl-compatability.sh
+
+"$HERE"/setup-procfs-knobs.sh
+"$HERE"/setup-limits.sh
+
+[[ -n $CUDA ]] && "$HERE"/setup-cuda.sh
+
+exit 0