feat: Add inputmode hint for mobile clients

[IvanBila]

Summary

This PR adds inputmode hint to the Cart list item and the Product Form, this change is aimed to improve user experience in mobile browsers, that way it displays the appropriate keyboard for the form input type being used(which in the particular case is numeric).

Preview

Current

Proposed

[sidharthachatterjee]

Love this! Thank you so much 💜

[gatsbot]

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