dashboard time display should respect local time format

[lucidNTR]

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

• Describe the issue you encountered:
  dashboard shows PM/AM time which is not used in germany, even though system time settings are set to 24h format

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

• Brave Version (revision SHA):
  6f9a4f2 latest master

• Steps to reproduce:

  1. open brave
  2. select 'Dashboard' as new tab option from settings
  3. open new tab

• Actual result:
  time is displayed in PM/AM format

• Expected result:
  time is displayed in localized format according to system settings

• 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?
  yes

• Can this issue be consistently reproduced?
  yes

[bsclifton]

Similar to #5647 (ideal solution would close both issues)