Update ViewedProduct.php

[mamsincl]

render final price as include tax

Description

klaviyo#312

Manual Testing Steps

Pre-Submission Checklist:

• You've updated the CHANGELOG following the steps here
• Internal Only - If this is a release, please confirm the following:
  • The links in the changelog have been updated to point towards the new versions
  • The version has been incremented in the following places: module.xml and composer.json

NOTE: Please use the Changelogger cli tool to manage versioned file upgrades.