fix: bats test refactoring (#1731)

Signed-off-by: Alexei Dodon <adodon@cisco.com>

test/blackbox/helpers_zot.bash

@@ -0,0 +1,48 @@
+ROOT_DIR=$(git rev-parse --show-toplevel)
+TEST_DATA_DIR=${ROOT_DIR}/test/data/
+OS=$(go env GOOS)
+ARCH=$(go env GOARCH)
+ZOT_PATH=${ROOT_DIR}/bin/zot-${OS}-${ARCH}
+ZLI_PATH=${ROOT_DIR}/bin/zli-${OS}-${ARCH}
+ZOT_MINIMAL_PATH=${ROOT_DIR}/bin/zot-${OS}-${ARCH}-minimal
+ZB_PATH=${ROOT_DIR}/bin/zb-${OS}-${ARCH}
+
+mkdir -p ${TEST_DATA_DIR}
+
+function zot_serve() {
+    local zot_path=${1}
+    local config_file=${2}
+    ${zot_path} serve ${config_file} &
+    # zot.pid file keeps a list of zot server PIDs (in case multiple zot servers are started)
+    echo -n "$! " >> ${BATS_FILE_TMPDIR}/zot.pid
+}
+
+# stops all zot instances started by the test
+function zot_stop_all() {
+    kill $(cat ${BATS_FILE_TMPDIR}/zot.pid)
+}
+
+function wait_zot_reachable() {
+    local zot_port=${1}
+    local zot_url=http://127.0.0.1:${zot_port}/v2/_catalog
+    curl --connect-timeout 3 \
+        --max-time 3 \
+        --retry 10 \
+        --retry-delay 0 \
+        --retry-max-time 60 \
+        --retry-connrefused \
+        ${zot_url}
+}
+
+function zli_add_config() {
+    local registry_name=${1}
+    local registry_url=${2}
+    if ! ${ZLI_PATH} config --list | grep -q main; then
+        ${ZLI_PATH} config add ${registry_name} ${registry_url}
+    fi
+}
+
+function zb_run() {
+    local zot_address=${1}
+    ${ZB_PATH} -c 10 -n 30 -o stdout ${zot_address} --skip-cleanup
+}