#258 Stop displaying the metabox when the order can't be found

[ahumulescu]

This PR:

• Adds a fix for the issue number #258

Steps to reproduce

• Go to WordPress admin -> WooCommerce -> Settings -> Advanced -> Features -> enable HPOS
• Go to an admin product page and scroll to the bottom of the page

Expected Result

• The TaxJar metabox not being displayed, as this is not an order page

After applying the PR, this should happen.

• The TaxJar metabox will be displayed only for the order pages

Click-Test Versions

• Woo 9.0

Specs Passing

• Woo 9.0

[CLAassistant]

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