Change default auto lock setting from 5 minutes to 10 minutes

[bbondy]

Many people have complained that we re-lock the wallet too quickly. Let's update from a default of 5 minutes auto-lock to a default of 10 minutes. Thread here: https://bravesoftware.slack.com/archives/C8MP8ME4C/p1666893856182529

[vadimstruts]

Hi @bbondy
Should we change default value only for new users or for new and all existing, who have the default value used (i.e. apply special preferences migration)?

[bbondy]

I think let's do the change, but please include someone from the security team on the review of the pull request.

It should just be a default value change, no migration.

[srirambv]

Verification passed on Oppo Reno 5 with Android 13 running 1.53.94 x64 Beta build

• Verified steps from issue description
• Verified new installs have a 10 mins timeout set as default
• Verified upgrading from an older install with a custom timeout set is retained
• Encountered #31077

26362.mp4

[srirambv]

Verification passed on

Brave	1.53.94 Chromium: 114.0.5735.133 (Official Build) beta (64-bit)
Revision	fbfa2ce68d01b2201d8c667c2e73f648a61c4f4a-refs/branch-heads/5735@{#1270}
OS	Windows 11 Version 22H2 (Build 22621.1848)

• Verified steps from issue description
• Verified new installs have a 10 mins timeout set as default
• Verified upgrading from an older install with a custom timeout set is retained
• Verified upgrading from an older install without changing timeout setting is updated to 10 mins as default

Clean install	Upgrade without timeout change	Upgrade with timeout change
26362.-.Clean.install.mp4	26362.-.Upgrade.with.no.change.mp4	26362.-.Upgrade.with.change.mp4