Errors: Activating special Gutenberg Build PR plugin

[paaljoachim]

Description

I have for a while used this approach: https://make.wordpress.org/design/2021/03/03/testing-a-gutenberg-pull-request-pr/
In PR: Going to the tab Checks -> clicking Gutenberg build -> then downloading the Gutenberg plugin -> unzipping -> zipping it up again -> uploading to a test site. Results in multiple fatal errors. So that I have to deactivate the plugin.

Step-by-step reproduction instructions

Follow this approach: https://make.wordpress.org/design/2021/03/03/testing-a-gutenberg-pull-request-pr/
and test these PR's: #32710 and #31109

Expected behaviour

No errors seen.

Actual behaviour

After activating the special Gutenberg PR build these errors are seen:

WordPress information

• WordPress version: WP 5.7.2
• Gutenberg version: Special Gutenberg plugin Build related to PR being tested.
• Are all plugins except Gutenberg deactivated? Yes
• Are you using a default theme (e.g. Twenty Twenty-One)? Yes

[paaljoachim]

Thanks @Mamaduka George!