Wiki "Repository cannot be checksummed because it does not exist" for geo

After upgrading 15.10.4 → 15.11.1, our "Project Wiki Repositories checksum progress" on the geo primary is stuck with ~55k failed. From geo.log:

…
{"severity":"ERROR","time":"2023-05-03T14:52:28.359Z","correlation_id":"35aaa2cf9ce4bf4bc68cf388b99f5615","class":"Geo::ProjectWikiRepositoryReplicator","gitlab_host":"git.drupalcode.org","message":"Repository cannot be checksummed because it does not exist","error":"Repository does not exist","replicable_name":"project_wiki_repository","replicable_id":83375}
{"severity":"ERROR","time":"2023-05-03T14:52:28.361Z","correlation_id":"35aaa2cf9ce4bf4bc68cf388b99f5615","class":"Projects::WikiRepository","gitlab_host":"git.drupalcode.org","message":"Error during verification","error":"Repository does not exist"}
{"severity":"ERROR","time":"2023-05-03T14:52:28.408Z","correlation_id":"35aaa2cf9ce4bf4bc68cf388b99f5615","class":"Geo::ProjectWikiRepositoryReplicator","gitlab_host":"git.drupalcode.org","message":"Repository cannot be checksummed because it does not exist","error":"Repository does not exist","replicable_name":"project_wiki_repository","replicable_id":78909}
{"severity":"ERROR","time":"2023-05-03T14:52:28.411Z","correlation_id":"35aaa2cf9ce4bf4bc68cf388b99f5615","class":"Projects::WikiRepository","gitlab_host":"git.drupalcode.org","message":"Error during verification","error":"Repository does not exist"}
{"severity":"ERROR","time":"2023-05-03T14:52:28.446Z","correlation_id":"35aaa2cf9ce4bf4bc68cf388b99f5615","class":"Geo::ProjectWikiRepositoryReplicator","gitlab_host":"git.drupalcode.org","message":"Repository cannot be checksummed because it does not exist","error":"Repository does not exist","replicable_name":"project_wiki_repository","replicable_id":79937}
{"severity":"ERROR","time":"2023-05-03T14:52:28.468Z","correlation_id":"35aaa2cf9ce4bf4bc68cf388b99f5615","class":"Projects::WikiRepository","gitlab_host":"git.drupalcode.org","message":"Error during verification","error":"Repository does not exist"}
…

Could be related to manual steps we took to mitigate #387980 (closed)

This is likely to have introduced the change #367925 (closed)