FIX Ensure eagerLoading don't load has_one twice (#11170)

[beerbohmdo]

Description

Currently if you call eagerLoad() to a list with repeating has_one objects only the last one will be eager loaded, the other will trigger a new database query.

This should fix this issue.

Manual testing steps

Issues

• BUG Eager loading with multiple objects pointing to the same has_one trigger extra db fetch #11170

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[GuySartorelli]

Retargetted to 5.2 and rebased.

[GuySartorelli]

LGTM, confirmed to fix the problem locally.
Thank you for taking the time to report and fix this, especially with unit testing.

I'll merge once CI has gone green.