swipe-tracker: Fix crash in confirm_swipe()

A regression from 03bd1145
11 jobs for wip/exalm/fix in 21 minutes and 38 seconds
Status Job ID Name Coverage
  Build
passed #246800
librem5
api-visibility

00:02:07

passed #246802
librem5
build-debian-clang

00:02:47

passed #246801
librem5
build-debian-gcc

00:02:22

passed #246803
librem5
build-fedora-gcc

00:08:01

 
  Test+Docs
passed #246804
librem5
build-gtkdoc

00:02:12

passed #246805
librem5
unit-test

00:02:11

43.2%
 
  Package
passed #246806
librem5
package-debian-buster

00:02:28

passed #246807
librem5:arm64
package-debian-buster:arm64

00:06:27

failed #246808
flatpak allowed to fail
package-flatpak

00:00:58

 
  Test Package
passed #246809
librem5
autopkgtest-debian-buster-package

00:02:32

passed #246810
librem5
lintian-debian-buster-package

00:01:02

 
Name Stage Failure
failed
package-flatpak Package
Committing stage finish to cache
Exporting sm.puri.Handy.Demo to repo
error: Writing content object: min-free-space-percent '3%' would be exceeded, at least 4.1?kB requested
Export failed: Child process exited with code 1
Uploading artifacts...
_build/meson-logs/meson-log.txt: found 1 matching files
WARNING: sm.puri.Handy.Demo-dev.flatpak: no matching files
Uploading artifacts to coordinator... ok
id=246808 responseStatus=201 Created token=6k5C6sD9
ERROR: Job failed: exit code 1