Dropdown shown when long pressing new tab will now show "New Tab"

[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).

Fixes #5703

Auditors: @bbondy

Test Plan:

1. Launch Brave and right click on the new tab button "+"
2. Click the "New Tab" item
3. Notice a new tab be created