add alert to slack in bash code example

Example: add alert to slack in bash

if curl -s --head --request GET https://abr.business.gov.au | grep "200 OK" > /dev/null; then
echo "https://abr.business.gov.au is UP"
else
echo "https://abr.business.gov.au is DOWN"
curl -X POST -H 'Content-type: application/json' --data '{"text":"https://abr.business.gov.au is DOWN"}' https://hooks.slack.com/services/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
fi