ci: Add missing docker.io prefix to CI_IMAGE_NAME_TAG

ci/test/00_setup_env_native_asan.sh

@@ -1,6 +1,6 @@
 #!/usr/bin/env bash
 #
-# Copyright (c) 2019-2022 The Bitcoin Core developers
+# Copyright (c) 2019-present The Bitcoin Core developers
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
@@ -17,7 +17,7 @@ fi
 
 export CONTAINER_NAME=ci_native_asan
 export PACKAGES="systemtap-sdt-dev clang-16 llvm-16 libclang-rt-16-dev python3-zmq qtbase5-dev qttools5-dev-tools libevent-dev libboost-dev libdb5.3++-dev libminiupnpc-dev libnatpmp-dev libzmq3-dev libqrencode-dev libsqlite3-dev ${BPFCC_PACKAGE}"
-export CI_IMAGE_NAME_TAG=ubuntu:23.04 # Version 23.04 will reach EOL in Jan 2024, and can be replaced by "ubuntu:24.04" (or anything else that ships the wanted clang version).
+export CI_IMAGE_NAME_TAG="docker.io/ubuntu:23.04"  # Version 23.04 will reach EOL in Jan 2024, and can be replaced by "ubuntu:24.04" (or anything else that ships the wanted clang version).
 export NO_DEPENDS=1
 export GOAL="install"
 export BITCOIN_CONFIG="--enable-c++20 --enable-usdt --enable-zmq --with-incompatible-bdb --with-gui=qt5 \