Unexpected behavior after changing the quantity on one line of the shipping address and clicking the Back button in the browser

[github-jira-sync-bot]

Preconditions:

• Magento EE 2.4.2-beta2 is installed
• A Simple product is created (TEST SIMPLE 1, price = $10)
• Create Customer with Shipping address
• Flat Rate shipping method is configured

Steps to Reproduce:

• 1. Go to the Storefront as the created Customer
• 2. Add the created Product to the Shopping Cart (2Qty)
• 3. Open the mini-cart
• 4. Click the View and Edit Cart link
• 5. Click the Check Out with Multiple Addresses link
• 6. Change Quantity in any line 
• 7.Click Go to Shipping Information button
• 8. Click the Back  button in browser (chrome) 

Expected results:

(/) The quantity should not change 

Actual results:

(x) A Quantity are incorrect

[github-jira-sync-bot]

The issue was exported from the internal JIRA. The link to the original JIRA issue: https://jira.corp.magento.com/browse/MC-40021

[m2-assistant]

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[m2-assistant]

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