fix ErrorBoundary fallbackUI prop type definition

[danfry1]

Description of the change

This updates the type definition for the ErrorBoundary's fallbackUI prop

Type of change

• Bug fix (non-breaking change that fixes an issue)

Related issues

Fixes #87

Checklists

Development

• Lint rules pass locally
• The code changed/added as part of this pull request has been covered with tests
• All tests related to the changed code pass in development

Code review

• This pull request has a descriptive title and information useful to a reviewer. There may be a screenshot or screencast attached
• "Ready for review" label attached to the PR and reviewers assigned
• Issue from task tracker has a link to this pull request
• Changes have been reviewed by at least one other engineer

[gazpachu]

Please, can we get this PR merged? 🙏

[gazpachu]

cc @rollbar-bborsits (Juanjo Marrón suggested to ping you) to have a look at this 🙏

[ghost]

Hey @gazpachu, thank you for your PR. Let me find someone internally to look into it.

[gazpachu]

@rollbar-bborsits it's not my PR, but thanks for the prompt response 🙇

[ghost]

@gazpachu You're right, I misspoken. Sorry about that. @danfry1 Thank you for the PR. We appreciate your efforts :)
In the meantime, I contacted @waltjones, who will take care of this soon.