Fix notice in _install_prepare_import() due to alternate approach to translations

This is very related to #3182660: [PP-1] Make translation filename pattern configurable during install →

Looks good :)

I'm triaging RTBC issues → . I read the IS, the comments and the MR. I didn't find any unanswered questions.

I left suggestions in the MR for coding standards. Plus I think a comment is needed so I had a go at that, perhaps someone has a better one.

I addressed @quietone's review. As the changes were minimal, setting back to rtbc.

The Needs Review Queue Bot → tested this issue. It no longer applies to Drupal core. Therefore, this issue status is now "Needs work".

This does not mean that the patch necessarily needs to be re-rolled or the MR rebased. Read the Issue Summary, the issue tags and the latest discussion here to determine what needs to be done.

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Fixed merge conflict.

Assigning to myself to commit tomorrow

Committed 220f04c and pushed to 11.x and 011f36a and pushed to 10.2.x. Thanks!

quietone → closed merge request !5714

Automatically closed - issue fixed for 2 weeks with no activity.