User wallets: brave browser creating multiple wallets

[mandar-brave]

For every single browser instance, currently the Brave browser is creating a new BAT card causing too many cards to be created against the same account.

Change asked for;

• Create card and set it to position-0 (starred)
• Card name set to "Brave Browser"
• Before creation, check 2 pages of account to see if BAT card called "Brave Browser"
• If no card exists, create card (there will be an issue if user renames card)

cc @NejcZdovc @kjozwiak

[mandar-brave]

@NejcZdovc besides starring the card, set position to 1 when card is created.

[GeetaSarvadnya]

Verification passed on

Brave	0.69.113 Chromium: 76.0.3809.100 (Official Build) beta (64-bit)
Revision	ed9d447d30203dc5069e540f05079e493fc1c132-refs/branch-heads/3809@{#990}
OS	Windows 10 OS Version 1803 (Build 17134.523)

• Verified the test plan from Single card brave-core#3072
• Verified Brave Browser card created when verifying wallet with new uphold account.
• Verified that no new Brave Browser card is created when verifying wallet with existing uphold account
• Verified Brave Browser card is picked from the list when connecting uphold with new/existing account

Verified passed with

Brave	0.69.114 Chromium: 76.0.3809.100 (Official Build) beta (64-bit)
Revision	ed9d447d30203dc5069e540f05079e493fc1c132-refs/branch-heads/3809@{#990}
OS	Mac OS X

• Verified the test plan from Single card brave-core#3072
• Verified Brave Browser card created when verifying wallet with new uphold account.
• Verified that no new Brave Browser card is created when verifying wallet with existing uphold account
• Verified Brave Browser card is picked from the list when connecting uphold with new/existing account. Verified by transferring BAT to Brave Browser card and verifying it displays as the wallet balance in the browser. Also verified by checking the address matches the uphold card id in the external_wallets section of Preferences file (default profile folder > preferences).

Verification passed on

Brave	0.69.114 Chromium: 76.0.3809.100 (Official Build) beta (64-bit)
Revision	ed9d447d30203dc5069e540f05079e493fc1c132-refs/branch-heads/3809@{#990}
OS	Ubuntu 18.04 LTS

• Verified the test plan from Single card brave-core#3072
• Verified Brave Browser card created when verifying wallet with new uphold account.
• Verified that no new Brave Browser card is created when verifying wallet with existing uphold account
• Verified Brave Browser card is picked from the list when connecting uphold with new/existing account