Warning message not displayed if custom value higher than entered value in routes generation page

[vkjr]

Followup to #20413

Steps:

1. Go to the routes generation page
2. Enter the value that is available on at least one network
3. Long press on the network when the route is built
4. Enter a value higher than the entered value on the routes generation page or higher than the maximum available value.

Actual result:

"This value is higher than entered send amount" is not shown

Expected result:

A warning message "This value is higher than entered send amount" should be displayed in cases:

• If the custom input is defined as 1 ETH and the routes generation value is defined as 0.9 ETH,
• If the value in custom input is higher than routes generation value and higher than amount available for this particular network.

OS:

IOS, Android

Devices:

• Pixel 7a, Android 13
• iPhone 11 Pro Max, IOS 17