Options for belongs_to does not contain primary_key in documentation

[gorn]

Chapter 4.1.2 of Active Record Associations documetation does not mention :primary_key option which however works as expected - giving the name of index column in the other table.

[rails-bot]

This issue has been automatically marked as stale because it has not been commented on for at least
three months.

The resources of the Rails team are limited, and so we are asking for your help.

If you can still reproduce this error on the 4-1-stable, 4-0-stable branches or on master,
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[gorn]

Still an issue in master. However girishso commit b5b773f fixes this, so it just needs to be pulled in.

[zzak]

This was fixed by #16698, thanks for the report!