Able to view ads after 426 Upgrade Required

[btlechowski]

Follow up to: #21388

User can view ads and be paid for them after 426.
After 426 from any end point we should stop serving ads

Steps to Reproduce

1. Override https://mywallet.ads.brave.com/v2/confirmation/payment/* response code to 426
2. Enable rewards and ads
3. View an ad
4. redeem the payment tokens -> will give 426
5. View an ad

Actual result:

User can view and be paid for ads
The UI indicates that this is not possible:

Expected result:

User is not served nor paid for ads till browser is upgraded

Reproduces how often:

Easily reproduced

Brave version (brave://version info)

Brave	1.41.94 Chromium: 103.0.5060.114 (Official Build) (64-bit)
Revision	a1c2360c5b02a6d4d6ab33796ad8a268a6128226-refs/branch-heads/5060@{#1124}
OS	Ubuntu 18.04 LTS

cc @brave/qa-team @tmancey @codomii @rebron @Miyayes @aseren

[tmancey]

Closing as resolved by #23958