As a suggestion for next time. Since Jira Core is included with the Jira Software installer you could save yourself some time and upgrade both at the same time by using the Jira software installer instead.
Also here are the upgrade notes for Jira Software 8.1.0:
Hi All! We’re excited to share the launch of an announcement banner that lets Jira site administrators communicate directly to their users across Jira Cloud instance. 📢 Get y...
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