[Follow up to #20967] Custom network is still removed when editing chainID when its not set as default

[srirambv]

Description

[Follow up to #20967] Custom network is still removed when editing chainID when its not set as default

Steps to reproduce

1. Install 1.37.42
2. Add a custom network
3. Set mainnet as default
4. Edit custom network chainID
5. Custom network is removed

Actual result

Network.removed.mp4

Expected result

Do not remove custom network. Should add a new entry for the changed value

Issue reproduces how often

Easy

Version/Channel Information:

• Can you reproduce this issue with the current Play Store version? NA
• Can you reproduce this issue with the current Play Store Beta version? NA
• Can you reproduce this issue with the current Play Store Nightly version? Yes

Device details

• Install type (ARM, x86): ARM
• Device type (Phone, Tablet, Phablet):All
• Android version: All

Brave version

1.37.42 nighlty build

Website problems only

• Does the issue resolve itself when disabling Brave Shields? NA
• Does the issue resolve itself when disabling Brave Rewards?NA
• Is the issue reproducible on the latest version of Chrome? nA

Additional information

cc: @SergeyZhukovsky

[srirambv]

Verification passed on the following devices running 1.36.100 x64 beta build

• Verified steps from issue description
• Verified editing custom EVM chain ID doesn't remove it
• Verified adding/editing chainID validates against the chainID and throws error message

Oppo Reno 5(Android 12)	Samsung Tab A (Android 10)
21046-Android.ARM.mp4	21046-Android.Tab.mp4