Fix: use fromSeconds when setting universalExpireTimer

[odpay]

First time contributor checklist:

• I have read the README and Contributor Guidelines
• I have signed the Contributor Licence Agreement

Contributor checklist:

• My contribution is not related to translations.
• My commits are in nice logical chunks with good commit messages
• My changes are rebased on the latest main branch
• A pnpm run ready run passes successfully (more about tests here)
• My changes are ready to be shipped to users

Description

When setting a "Default timer for new chats", DurationInSeconds.fromSeconds(newValue) should be used instead of fromMillis as the newValue number is in seconds. Otherwise the following bug occurs:

Tested on macOS 10.15.7 (Signal Desktop: 7.59.0):
To recreate this bug, simply:

1. open Settings -> Privacy,
2. set the "Default timer for new chats" to any set/custom value from the dropdown menu, (e.g. '1 week'),
3. notice how the default timer is instead set to 0.001 times your selected value (1 week -> 10 minutes, 4 seconds)

This PR fixes this behaviour.

[indutny-signal]

Thank you! We merged this PR internally and will push it to this repository with the next release (likely later today).