Closing update dialog force update instead of postponing it

[MonoS]

Bug description

When the update dialog show up at startup closing it will update the application instead of postponing

Steps to reproduce

1. use an old version
2. the update dialog show up
3. close the dialog

Actual result:
The update is executed

Expected result:
The update should be postponed

Platform info

Signal version: 1.16.3

Operating System:

Windows 10 1803 x64

[Herohtar]

This is still an issue in v1.29.6.

Specifically, the showUpdateDialog function is configuring the message box options to use RESTART_BUTTON as the cancelId.

Signal-Desktop/ts/updater/common.ts

Line 160 in 6cd3165

cancelId: RESTART_BUTTON,

According to the dialog.showMessageBox documentation, cancelId is "The index of the button to be used to cancel the dialog, via the Esc key." This is the equivalent of clicking the close button (X).

Restarting Signal and applying the update is not cancelling, and is not the behavior people expect when clicking close or pressing Esc on the update dialog.

cancelId should be set to LATER_BUTTON instead.