pp-chat-info: Set transient window

So that the file chooser dialog is properly shown
7 jobs for wip/sadiq/set-transient-for in 9 minutes and 58 seconds (queued for 1 second)
Status Job ID Name Coverage
  Build
passed #369840
librem5
build-pureos-gcc-byzantium

00:01:48

 
  Test
passed #369842
librem5
check-po

00:00:15

passed #369841
librem5
test:debian-gcc

00:02:38

21.5%
 
  Package
passed #369843
librem5
package-pureos-byzantium

00:01:49

passed #369844
librem5:arm64
package-pureos-byzantium:arm64

00:05:31

 
  Test Package
passed #369845
librem5
autopkgtest-pureos-byzantium-package

00:01:17

passed #369846
librem5
lintian-pureos-byzantium-package

00:00:36