Function trimPostalCode

trimPostalCode(postalCode: string, maxLength?: number): string
Normalizes a postal code to a 5-digit format.
Parameters
- postalCode: string
  The postal code to normalize.
- maxLength: number = 5
  The maximum length of the postal code.
Returns string
The normalized postal code.
Example
```
trimPostalCode("10001-1234"); // "10001"
trimPostalCode("10001-1234", 9); // "10001-1234"
```
- Defined in utils/address/postalCodes.ts:11