chore: Force license uuids to not be null (#6012)

* chore: Force license uuids to not be null

* All unit tests generate uuids for licenses

* Update migration files to new numbers

* Put migration in transaction

coderd/database/models.go

@@ -1288,8 +1288,8 @@ type License struct {
 	UploadedAt time.Time `db:"uploaded_at" json:"uploaded_at"`
 	JWT        string    `db:"jwt" json:"jwt"`
 	// exp tracks the claim of the same name in the JWT, and we include it here so that we can easily query for licenses that have not yet expired.
-	Exp  time.Time     `db:"exp" json:"exp"`
-	Uuid uuid.NullUUID `db:"uuid" json:"uuid"`
+	Exp  time.Time `db:"exp" json:"exp"`
+	UUID uuid.UUID `db:"uuid" json:"uuid"`
 }
 
 type Organization struct {