Global-jjb script:

jenkins-init-scripts/lf-env.sh

...has an error here:

lf-git-validate-jira-urls () {
    echo "Checking for JIRA URLs in commit message..."
    # if JIRA_URL is not defined, nothing to do
    if [[ -v JIRA_URL ]]; then
        base_url=$(echo "$JIRA_URL" | awk -F'/' '{print $3}')

Which should have a dollar before the variable name:

lf-git-validate-jira-urls () {
    echo "Checking for JIRA URLs in commit message..."
    # if JIRA_URL is not defined, nothing to do
    if [[ -v $JIRA_URL ]]; then
        base_url=$(echo "$JIRA_URL" | awk -F'/' '{print $3}')