Executing "sudo apport-bug /var/crash/some-path.crash" leads to "ERROR: Cannot update /var/crash/some-path.crash: [Errno 13] Permission denied" very often

Steps to reproduce:
1. Have Ubuntu 20.04 LTS installed
2. Get some crash file of crashed application (in my example it was /var/crash/_usr_lib_mate-panel_clock-applet.1000.crash )
3. Try to send this crash file to launchpad using `sudo apport-bug /var/crash/_usr_lib_mate-panel_clock-applet.1000.crash`

Expected results:
* apport opened window about sending the crash report and then opened Firefox allowing user to login to Launchoad and then to fill some details about the bug-report

Actual results:
* apport opened window about sending the crash, but Firefox is not opened; instead shows the error in the terminal

```
$ sudo apport-bug /var/crash/_usr_lib_mate-panel_clock-applet.1000.crash
[sudo] password for mate:
ERROR: Cannot update /var/crash/_usr_lib_mate-panel_clock-applet.1000.crash: [Errno 13] Permission denied: '/var/crash/_usr_lib_mate-panel_clock-applet.1000.crash'

```

Note: what is interesting in this case the upload was successful:

```
$ ls -alt /var/crash/
total 5252
-rw------- 1 whoopsie whoopsie 37 May 7 23:19 _usr_lib_mate-panel_clock-applet.1000.uploaded
drwxrwsrwt 2 root whoopsie 4096 May 7 23:19 .
-rw-r--r-- 1 root whoopsie 0 May 7 23:19 _usr_lib_mate-panel_clock-applet.1000.upload
-rw-r----- 1 mate whoopsie 5364223 May 7 23:12 _usr_lib_mate-panel_clock-applet.1000.crash
drwxr-xr-x 14 root root 4096 Apr 23 10:48 ..

```

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: apport 2.20.11-0ubuntu27
ProcVersionSignature: Ubuntu 5.4.0-26.30-generic 5.4.30
Uname: Linux 5.4.0-26-generic x86_64
ApportLog:
 ERROR: apport (pid 2675) Thu May 7 23:10:51 2020: called for pid 2659, signal 11, core limit 0, dump mode 1
 ERROR: apport (pid 2675) Thu May 7 23:10:51 2020: executable: /usr/lib/mate-panel/clock-applet (command line "/usr/lib/mate-panel/clock-applet")
 ERROR: apport (pid 2675) Thu May 7 23:10:51 2020: debug: session gdbus call: (true,)

 ERROR: apport (pid 2675) Thu May 7 23:10:54 2020: wrote report /var/crash/_usr_lib_mate-panel_clock-applet.1000.crash
ApportVersion: 2.20.11-0ubuntu27
Architecture: amd64
CasperMD5CheckResult: skip
CrashReports:
 600:121:127:37:2020-05-07 23:19:38.692947366 +0300:2020-05-07 23:11:44.888143341 +0300:/var/crash/_usr_lib_mate-panel_clock-applet.1000.uploaded
 644:0:127:0:2020-05-07 23:19:37.976589335 +0300:2020-05-07 23:19:37.976589335 +0300:/var/crash/_usr_lib_mate-panel_clock-applet.1000.upload
 640:1000:127:5364223:2020-05-07 23:12:22.348865032 +0300:2020-05-07 23:19:44.571885615 +0300:/var/crash/_usr_lib_mate-panel_clock-applet.1000.crash
CurrentDesktop: MATE
Date: Thu May 7 23:20:20 2020
InstallationDate: Installed on 2020-04-23 (14 days ago)
InstallationMedia: Ubuntu-MATE 20.04 LTS "Focal Fossa" - Release amd64 (20200423)
PackageArchitecture: all
SourcePackage: apport
UpgradeStatus: No upgrade log present (probably fresh install)