Time tracker uses wrong warning icon
Since the icon cleanup in #49112 the icon_warning.gif does not exist anymore.
Therefore the timetracker output in the admin panel should use icon_warning2.gif
[BUGFIX] Use correct warning icon in time tracker
The icon_warning2.gif is used instead of the deleted icon_warning.gif.
Reviewed-by: Xavier Perseguers
Tested-by: Xavier Perseguers
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn