fix(typings): add date to where (#11612)

types/lib/model.d.ts

@@ -341,6 +341,7 @@ export type WhereValue =
   | string // literal value
   | number // literal value
   | boolean // literal value
+  | Date // literal value
   | Buffer // literal value
   | null
   | WhereOperators

types/test/where.ts

@@ -22,6 +22,7 @@ where = {
   buffer: Buffer.alloc(0),
   buffers: [Buffer.alloc(0)],
   null: null,
+  date: new Date()
 };
 
 // Operators