Add constraints to user_agent_details.organization_id with NOT VALID

What does this MR do and why?

This change adds a NOT NULL constraint to the user_agent_details.organization_id column.

sec: == 20251209230404 AddNotNullConstraintToUserAgentDetailsOnOrganizationId: migrating 
sec: -- current_schema(nil)
sec:    -> 0.1087s
sec: -- transaction_open?(nil)
sec:    -> 0.0000s
sec: -- transaction_open?(nil)
sec:    -> 0.0000s
sec: -- execute("ALTER TABLE user_agent_details\nADD CONSTRAINT check_17a3a18e31\nCHECK ( organization_id IS NOT NULL )\nNOT VALID;\n")
sec:    -> 0.1028s
sec: == 20251209230404 AddNotNullConstraintToUserAgentDetailsOnOrganizationId: migrated (2.8367s) 

https://ops.gitlab.net/gitlab-com/database-team/gitlab-com-database-testing/-/jobs/21607446

References

• #553472

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