[CDX-217] Add Sale Price Conditional Check

[evanyan13]

Objective

• As user of PLP library I want to add a conditional check to safeguard against situations where we are mistakenly passing the same value to both sale_price and price
• As CDX, I want to implement a logic to only render sale_price when it is strictly less than price

Definition of Done

• Add conditional check to only render sale_price and its UI when it is strictly less than price
• Add tests

[TarekAlQaddy]

Thanks @evanyan13 for working on that!
I left some minor comments, please let me know what you think

[TarekAlQaddy]

Approved with a minor comment, please let me know what you think

[Mudaafi]

Thanks for making the PR! A small edge case consideration before we ship this.

[evanyan13]

Hi @Mudaafi
Thank you for the review!
I have addressed some of the lint issues.
Have also left my comment for the edge case consideration. Would like to hear your thoughts about it!

[Mudaafi]

lgtm, thanks for making the changes!