chore(develop): release blockly 8.1.0

[release-please]

🤖 I have created a release beep boop

8.1.0 (2022-04-21)

Features

• Add margin around zoomToFit (#6042) (a202558)

Bug Fixes

• dragging fails for collapsed blocks with Icons, which have been … (#6081) (5240301)
• Fix compilation errors under Closure's strict mode (#6073) (edc2a5c)
• fix message loading from script tags (#6060) (44edbb8)
• improve types in touch code (#6099) (7c7cfbe)
• mutators disconnecting from children instead of moving them (#6047) (493444c)
• Silence Closure errors when modifying tooltips. (#6098) (29b6b87)
• type error in uneditable bubbles (#6092) (7353c61)
• update extraState property in serializer typedefs (#6057) (55cae6e)

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[github-actions]

Thanks for the PR! The develop branch is currently frozen in preparation for the release so it may not be addressed until after release week.

[release-please]

🤖 Release is at https://github.com/alschmiedt/blockly/releases/tag/untagged-087052dcd629169373d6 🌻