projects/sequelize-ts: example updates violate rules

[chinhnguyenh]

No description provided.

[github-actions]

atlas schema lint on env://url

Status	Rule	Result
	Rule "unique-non-id-column"	Tables must have a unique non-id column Table universities must have a unique non-id column /home/runner/work/atlas-showcase/atlas-showcase/projects/sequelize-ts/src/models/University.ts:4:0
	Rule "foreign-key-not-nullable"	Foreign keys must not be nullable Foreign key 0 must not be nullable /home/runner/work/atlas-showcase/atlas-showcase/projects/sequelize-ts/src/models/Department.ts:5:0
	Rule "foreign-key-postfix-id"	Foreign keys must have a column name ending with '_id' Foreign key 1 must have a column name ending with 'Id' /home/runner/work/atlas-showcase/atlas-showcase/projects/sequelize-ts/src/models/Student.ts:4:0