CI: Eliminating dependency on clone_tests_repo()

As part of archiving the tests repo, we are eliminating the dependency on
`clone_tests_repo()`. The scripts using the function is as follows:

- `ci/install_rust.sh`.
- `ci/setup.sh`
- `ci/lib.sh`

This commit removes or replaces the files, and makes an adjustment accordingly.

Signed-off-by: Hyounggyu Choi <Hyounggyu.Choi@ibm.com>

tests/integration/kubernetes/confidential_kbs.sh

@@ -11,7 +11,7 @@ kubernetes_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 # shellcheck disable=1091
 source "${kubernetes_dir}/../../gha-run-k8s-common.sh"
 # shellcheck disable=1091
-source "${kubernetes_dir}/../../../ci/lib.sh"
+source "${kubernetes_dir}/../../../tests/common.bash"
 
 KATA_HYPERVISOR="${KATA_HYPERVISOR:-qemu}"
 # Where the trustee (includes kbs) sources will be cloned