package openjdk-14-jre-headless:amd64 14.0.1+7-1ubuntu1 failed to install/upgrade: installed openjdk-14-jre-headless:amd64 package post-installation script subprocess returned error exit status 2

[Stefan Strömer]

apt ist complaining about openjdk not being configured
After installing openjdk I got this message for the first time
Now I get it each time running apt install or apt update

ProblemType: Package
DistroRelease: Ubuntu 20.04
Package: openjdk-14-jre-headless:amd64 14.0.1+7-1ubuntu1
ProcVersionSignature: Ubuntu 5.4.0-47.51-generic 5.4.55
Uname: Linux 5.4.0-47-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.8
AptOrdering:
 chromium-browser-l10n:amd64: Install
 NULL: ConfigurePending
Architecture: amd64
CasperMD5CheckResult: skip
Date: Tue Sep 8 20:58:44 2020
DuplicateSignature:
 package:openjdk-14-jre-headless:amd64:14.0.1+7-1ubuntu1
 Setting up openjdk-14-jre-headless:amd64 (14.0.1+7-1ubuntu1) ...
 update-alternatives: error: alternative keytool can't be master: it is a slave of jar
 dpkg: error processing package openjdk-14-jre-headless:amd64 (--configure):
  installed openjdk-14-jre-headless:amd64 package post-installation script subprocess returned error exit status 2
ErrorMessage: installed openjdk-14-jre-headless:amd64 package post-installation script subprocess returned error exit status 2
InstallationDate: Installed on 2017-09-11 (1093 days ago)
InstallationMedia: Ubuntu 17.04 "Zesty Zapus" - Release amd64 (20170412)
Python3Details: /usr/bin/python3.8, Python 3.8.2, python3-minimal, 3.8.2-0ubuntu2
PythonDetails: /usr/bin/python2.7, Python 2.7.18rc1, python-is-python2, 2.7.17-4
RelatedPackageVersions:
 dpkg 1.19.7ubuntu3
 apt 2.0.2ubuntu0.1
SourcePackage: openjdk-14
Title: package openjdk-14-jre-headless:amd64 14.0.1+7-1ubuntu1 failed to install/upgrade: installed openjdk-14-jre-headless:amd64 package post-installation script subprocess returned error exit status 2
UpgradeStatus: Upgraded to focal on 2020-08-12 (27 days ago)