[Desktop] need to refresh brave://rewards page to see correct backup modal after restoring an anon user wallet

[LaurenWags]

Description

Found while testing #10021

After restoring an anon user wallet, I needed to refresh brave://rewards page to see the correct backup modal.

Steps to Reproduce

1. Install 1.12.x, enable rewards
2. Restore an anon user wallet with BAT
3. Wait for OnFetch call back in terminal
4. Open Backup modal

Actual result:

Expected result:

Since I restored a wallet with BAT, I should see the below (with words, I blanked those out). Page refresh fixes this.

Reproduces how often:

easily

Brave version (brave://version info)

Brave	1.12.108 Chromium: 84.0.4147.105 (Official Build) (64-bit)
Revision	a6b12dfad6663f13a7e16e9a42a6a4975374096b-refs/branch-heads/4147@{#943}
OS	macOS Version 10.14.6 (Build 18G3020)

Version/Channel Information:

• Can you reproduce this issue with the current release? n/a for 1.11.x, yes for 1.12.x
• Can you reproduce this issue with the beta channel? no for 1.13.x
• Can you reproduce this issue with the nightly channel? no for 1.14.x

Other Additional Information:

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

Miscellaneous Information:

cc @NejcZdovc @brave/legacy_qa

[GeetaSarvadnya]

Reproduced in Windows 10 x64 - 1.12.108