package mysql-server-5.7 5.7.25-0ubuntu0.16.04.2 failed to install/upgrade: subprocess installed post-installation script returned error exit status 1

[Mr H Lewis]

This bug report occured automatically. I did not instigate the bug report.

ProblemType: Package
DistroRelease: Ubuntu 16.04
Package: mysql-server-5.7 5.7.25-0ubuntu0.16.04.2
ProcVersionSignature: Ubuntu 4.15.0-47.50~16.04.1-generic 4.15.18
Uname: Linux 4.15.0-47-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.18
Architecture: amd64
Date: Tue Apr 2 19:10:16 2019
ErrorMessage: subprocess installed post-installation script returned error exit status 1
InstallationDate: Installed on 2018-01-04 (454 days ago)
InstallationMedia: Ubuntu 16.04.3 LTS "Xenial Xerus" - Release amd64 (20170801)
Logs.var.log.daemon.log:

MySQLConf.etc.mysql.conf.d.mysql.cnf: [mysql]
MySQLConf.etc.mysql.conf.d.mysqldump.cnf:
 [mysqldump]
 quick
 quote-names
 max_allowed_packet = 16M
MySQLConf.etc.mysql.mysql.conf.d.mysqld_safe_syslog.cnf:
 [mysqld_safe]
 syslog
MySQLVarLibDirListing: ['mysql', 'ib_logfile0', 'Hospital', 'debian-5.7.flag', 'ibdata1', 'ib_buffer_pool', 'auto.cnf', 'sys', 'ib_logfile1', 'mysql_upgrade_info', 'performance_schema']
ProcCmdline: BOOT_IMAGE=/boot/vmlinuz-4.15.0-47-generic root=UUID=abf00d4e-7ee9-4c72-897b-c2f355cf4ba1 ro quiet splash vt.handoff=7
RelatedPackageVersions:
 dpkg 1.18.4ubuntu1.5
 apt 1.2.31
SourcePackage: mysql-5.7
Title: package mysql-server-5.7 5.7.25-0ubuntu0.16.04.2 failed to install/upgrade: subprocess installed post-installation script returned error exit status 1
UpgradeStatus: Upgraded to xenial on 2019-04-02 (0 days ago)
modified.conffile..etc.mysql.mysql.cnf: [modified]
modified.conffile..etc.mysql.mysql.conf.d.mysqld.cnf: [modified]
mtime.conffile..etc.mysql.mysql.cnf: 2018-01-29T15:50:16.322825
mtime.conffile..etc.mysql.mysql.conf.d.mysqld.cnf: 2018-01-25T14:30:45.913590