Fix phone number input field to restrict letters and accept only numbers and allowed symbols

[akshay0611]

The phone number input field was previously accepting letters, which could lead to invalid data being submitted. To resolve this, the input field has been updated with the following changes:

• Pattern validation has been added to allow only numbers and the symbols + and -.
  - inputmode="numeric" is used to display the numeric keyboard on mobile devices.
• onkeypress event has been added to restrict keypress input to numbers and the allowed symbols.``