Adding CoingecoID should only show the value for the selected asset rather than at portfolio

[srirambv]

Description

Adding CoingecoID should only show the value for the selected asset rather than at portfolio. Found while testing #20581

Steps to Reproduce

1. Add a custom asset view
2. Add bitcoin for CoingeckoID in the custom asset details
3. Entire portfolio and other existing tokens values are listed in BTC value rather than the one that is added

Actual result:

Adding CoingecoID should only show the value for the selected asset rather than at portfolio

Expected result:

Should only show for the custom token that is added

Reproduces how often:

Easy

Brave version (brave://version info)

Brave	1.36.100 Chromium: 98.0.4758.102 (Official Build) beta (x86_64 translated)
Revision	273bf7ac8c909cde36982d27f66f3c70846a3718-refs/branch-heads/4758@{#1151}
OS	All

Version/Channel Information:

• Can you reproduce this issue with the current release? NA
• Can you reproduce this issue with the beta channel? Yes
• Can you reproduce this issue with the nightly channel? Yes

Other Additional Information:

• 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

Miscellaneous Information:

cc: @Douglashdaniel @onyb

[Douglashdaniel]

Per internal discussion this is expected behavior.
CoingeckoID is for used for getting the accurate price for a token and was added as an option since symbols don't always return the correct price information from our API.
Adding Bitcoin as a CoingeckoID is going to reflect as the price for that token.