Fix organizations model inheritance

What does this MR do and why?

Fix organizations model inheritance

• according to https://docs.gitlab.com/ee/development/database/multiple_databases.html#gitlab-schema this needs to change to reflect the clusterwide that it is in https://gitlab.com/gitlab-org/gitlab/-/blob/9a74a3c9b6e669d338ce5d1df9edddd1f981b1b1/db/docs/organizations.yml#L10-10

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Related to #436015 (closed)