Its not going to be possible to do this in JIRA Cloud.
With JIRA Server, you can leverage the Script Runner add-on: https://marketplace.atlassian.com/plugins/com.onresolve.jira.groovy.groovyrunner
For more details, please reference this previously posted questions - they aren't identical but are similar in nature:
Hey Community mates! Claire here from the Software Product Marketing team. We all know software development changes rapidly, and it's often tough to keep up. But from our research, we've found the h...
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