ALTER TABLE ... IMPORT TABLESPACE causes innodb_fatal_semaphore_wait_threshold was exceeded for dict_sys.latch.

Attempting a partial restore from `mariabackup` using https://github.com/tvogel/run-mariabackup leads the mariadbd to abort during running
```
ALTER TABLE .... IMPORT TABLESPACE;
```

I will attach the log entry from `error.log` and will upload an all-thread stack-trace with symbols to private FTP under this issue number because of sensitive data in the back-trace.