Ledger calculation when 0 eligible unpinned sites

[NejcZdovc]

Test Plan

#8103 (comment)

• Go to payments and add two publishers
• Pin one and exclude the second one
• Set 60 % for a pinned publisher
• Value should be adjusted to 100%

Automated test plan

npm run test -- --grep="check pinned sites amount, when you have 0 eligible unpinned sites"

• Did you search for similar issues before submitting this one?
  yes

• Describe the issue you encountered:
  Calculation in the ledger table is wrong when you don't have any eligible unpinned sites and you set custom % for a pinned site that is bellow 100%.

• Platform (Win7, 8, 10? macOS? Linux distro?):
  all

• Brave Version (revision SHA):
  7080042

• Steps to reproduce:

  1. Go to payments and add two publishers
  2. Pin one and exclude the second one
  3. Set 60 % for a pinned publisher

• Actual result:
  Value stays the same, 60%

• Expected result:
  Value should be changed to 100%

• Will the steps above reproduce in a fresh profile? If not what other info can be added?
  yes

• Is this an issue in the currently released version?
  no

• Can this issue be consistently reproduced?
  yes

• Screenshot if needed:
  

• Any related issues:
  Allow user to pin their favorite sites in Brave Payments (and other UI tweaks) #7347

[luixxiul]

To QA testers: 077a60c of #8103 is not yet available on 0.14.1 Preview 1