undefined method `iid'

Hey! While running on repo with no MR's opened I got this in logs:

[2021-02-09 05:05:52 +0000 tid=goks6bqwd] WARN: NoMethodError: undefined method `iid' for nil:NilClass
[2021-02-09 05:05:52 +0000 tid=goks6bqwd] WARN: /home/dependabot/app/services/dependabot/merge_request_service.rb:155:in `superseeded_mrs'
/home/dependabot/app/services/dependabot/merge_request_service.rb:69:in `close_superseeded_mrs'

I don't really know ruby, but based on what I saw there should be no iteration over what superseeded_mrs returns. For me it looks like superseeded_mrs returns strange things.

No MR was created, even when there were update findings: found version for update: org.springframework.cloud:spring-cloud-starter-contract-stub-runner 2.1.1.RELEASE => 3.0.1