Fix about:brave; version information is always set (regardless of errors)

[bsclifton]

• Submitted a ticket for my issue if one did not already exist.
• Used Github auto-closing keywords in the commit message.
• Added/updated tests for this change (for new code or code which already has tests).
• Ran git rebase -i to squash commits (if needed).

Version information is always set (regardless of errors).

Code itself is now fault tolerant as well. Includes tests.

Fixes: #5633

Auditors: @jonathansampson, @bbondy

Manual test plan:

1. Move your session out of the way (or do a fresh install)
2. Launch Brave
3. Go to about:brave
4. Notice version shows as expected

Automated test plan:
run npm run test -- --grep="about:brave tests"

[jonathansampson]

LGTM

[bsclifton]

BTW- meant to document this; The reason the version wasn't showing:
When the app loads for the first time, the session does not exist. When it tries to load, it fails because it's trying to process undefined.