Fix param names in RelatedLinksCreateWorker

What does this MR do and why?

Fixes RelatedLinksCreateWorker (added in !133107 (merged)) because the records were not being loaded due to params not being set properly (the instance variable was shadowed by the argument variable).

The tests didn't fail because they contained the param keys as symbols while the worker set them as strings.

Screenshots or screen recordings

Screen_Recording_2023-10-17_at_13.20.48

MR acceptance checklist

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Related to #419555 (closed)