Improved: enable ion-spinner on 'Regenerate Shipping Label' Action in Completed Tab & upgrade the @hotwax/app-theme version(#678)

[R-Sourabh]

Related Issues

#678

Short Description and Why It's Useful

• Instead of using a function that lists the completed orders after cloning the completedOrders getter, which was not showing reactivity when changing the properties of an order, I replaced that function with a variable that maintains a cloned list of completed orders.
• Additionally, I updated the @hotwax/app-theme version to apply CSS to the ion-spinner inside the ion-button.

Screenshots of Visual Changes before/after (If There Are Any)

Contribution and Currently Important Rules Acceptance

• I read and followed contribution rules