[WEB] [JS-Register-Basic Details] Lack of Validation for Mobile Number in JobSeeker Registration

**Steps:**
1. Open a web browser and navigate to the website: "https://dearjob.org".
2. On the website's homepage, locate and click on the "Register" link in the menu tab.
3. From the available registration options, choose "JobSeeker."
4. On the "Basic Details" section of the registration form, find the field for entering a mobile number.
5. Attempt to enter spaces, different special characters (e.g., @, #, $), and submit the form using the "Save and Next" button.

**Actual Result:**
The mobile number field in the JobSeeker registration form allows the entry of spaces, different special characters, and does not have any validation in place. Users can enter these characters as the mobile number, and the "Save and Next" button remains enabled. There is no error message or validation feedback provided for these entries.

**Expected Result:**
1. The mobile number field in the JobSeeker registration form should have validation to ensure that users enter a valid mobile number.
2. Validation should prevent the entry of spaces, different special characters, or any invalid characters in the mobile number field.
3. When these types of entries are attempted, appropriate error messages should be displayed.
4. The "Save and Next" button should remain disabled until a valid mobile number is entered.