Fix shadowDom hooks out of date.

[squid-ney]

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✔️ Checklist

• A changeset describing the change and affected packages. (more info)
• Added or updated documentation
• Tests for new functionality and regression tests for bug fixes
• Screenshots attached (for UI changes)
• All your commits have a Signed-off-by line in the message. (more info)

[backstage-goalie]

Missing Changesets

The following package(s) are changed by this PR but do not have a changeset:

• @backstage/plugin-techdocs-react
• @backstage/plugin-techdocs

See CONTRIBUTING.md for more information about how to add changesets.

Changed Packages

Package Name	Package Path	Changeset Bump	Current Version
@backstage/plugin-techdocs-react	plugins/techdocs-react	none	v1.2.5-next.2
@backstage/plugin-techdocs	plugins/techdocs	none	v1.10.6-next.2

[backstage-goalie]

Thanks for the contribution!
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