fix(types): allow rangable to take a string tuple (#13486)

Co-authored-by: Sascha Depold <sdepold@users.noreply.github.com>

types/lib/model.d.ts

@@ -131,7 +131,7 @@ export interface AllOperator {
   [Op.all]: readonly (string | number | Date | Literal)[];
 }
 
-export type Rangable = readonly [number, number] | readonly [Date, Date] | Literal;
+export type Rangable = readonly [number, number] | readonly [Date, Date] | readonly [string, string] | Literal;
 
 /**
  * Operators that can be used in WhereOptions

types/test/where.ts

@@ -227,7 +227,7 @@ MyModel.findAll({
       [Op.lt]: 10, // id < 10
       [Op.lte]: 10, // id <= 10
       [Op.ne]: 20, // id != 20
-      [Op.between]: [6, 10] || [new Date(), new Date()], // BETWEEN 6 AND 10
+      [Op.between]: [6, 10] || [new Date(), new Date()] || ["2020-01-01", "2020-12-31"], // BETWEEN 6 AND 10
       [Op.notBetween]: [11, 15], // NOT BETWEEN 11 AND 15
       [Op.in]: [1, 2], // IN [1, 2]
       [Op.notIn]: [1, 2], // NOT IN [1, 2]