* Regenerate default profile picture if username has changed
- Only actions is profile picture has not been changed
- Adjusts ResetLastPictureUpdate store function to store
-curTime instead of 0
- This is to support updating the default picture while still
retaining the ability to discern a default image from a set one.
- Changes SetDefaultProfileImage to leverage UpdateDefaultProfileImage
- Test updates around updating user default profile pictures
* App interface updates
* Only display picture update date if non-negative
- Ensures we don't display negative timestamps (default images)
- Change ported for mono-repo changes
* Remove duplicate test assertion
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Co-authored-by: Nathan Geist <ngeist@spiria.com>
Co-authored-by: Mattermost Build <build@mattermost.com>