Install Script Exits Prematurely on Debian 10

[benr]

On Debian 10 errors can be thrown that cause the installer to quit even though install would proceed fine. Here is an example of the script failing:

...
* Installing mondoo package for cnquery and cnspec
Hit:1 http://security.debian.org/debian-security buster/updates InRelease
Hit:2 http://cdn-aws.deb.debian.org/debian buster InRelease
Hit:3 http://cdn-aws.deb.debian.org/debian buster-updates InRelease
Ign:4 http://cdn-aws.deb.debian.org/debian buster-backports InRelease
Err:5 http://cdn-aws.deb.debian.org/debian buster-backports Release
  404  Not Found [IP: 18.160.46.41 80]
Get:6 https://releases.mondoo.com/debian stable InRelease [17.3 kB]
Get:7 https://releases.mondoo.com/debian stable/main amd64 Packages [3113 B]
Reading package lists... Done
E: The repository 'http://cdn-aws.deb.debian.org/debian buster-backports Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
The mondoo package for cnquery and cnspec install script encountered a problem. For assistance, please join our community on GitHub Discussions.

However, if you install immediately thereafter:

$ sudo apt install mondoo -y
sudo: unable to resolve host cache-4: Name or service not known
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following additional packages will be installed:
  cnquery cnspec
The following NEW packages will be installed:
  cnquery cnspec mondoo
0 upgraded, 3 newly installed, 0 to remove and 81 not upgraded.
Need to get 38.6 MB of archives.
After this operation, 123 MB of additional disk space will be used.
Get:1 https://releases.mondoo.com/debian stable/main amd64 cnquery amd64 11.51.1 [16.6 MB]
Get:2 https://releases.mondoo.com/debian stable/main amd64 cnspec amd64 11.51.1 [22.0 MB]
Get:3 https://releases.mondoo.com/debian stable/main amd64 mondoo all 11.51.1 [586 B]
Fetched 38.6 MB in 2s (20.8 MB/s)
Selecting previously unselected package cnquery.
(Reading database ... 24367 files and directories currently installed.)
Preparing to unpack .../cnquery_11.51.1_amd64.deb ...
Unpacking cnquery (11.51.1) ...
Selecting previously unselected package cnspec.
Preparing to unpack .../cnspec_11.51.1_amd64.deb ...
 -> Prepare for cnspec installation
Unpacking cnspec (11.51.1) ...
Selecting previously unselected package mondoo.
Preparing to unpack .../mondoo_11.51.1_all.deb ...
Unpacking mondoo (11.51.1) ...
Setting up cnquery (11.51.1) ...
Setting up cnspec (11.51.1) ...
 -> Migrate cnspec configuration
! can't find any paths for providers, none are configured system-path=/opt/mondoo/providers
→ No migration needed.
Setting up mondoo (11.51.1) ...

Works fine.